Thursday, December 12, 2013

Field Records Remain Valuable in Establishing Reliability of Tracking Dogs (unlike Drug Dogs after Florida v. Harris)

The American legal history of tracking goes back to the dark days of slavery, as discussed by us elsewhere.  That tradition produced a case law, and principles of evidence, very different from what began to arise in the 1970s for narcotics and explosives detection dogs.  Tracking dogs were often trained as an economic activity, and well-known dogs could be brought over state lines—sometimes over several state lines—to track in notorious criminal cases.  There was also a long tradition of prisoners training dogs, dogs that would be used to follow the trails of fellow prisoners who tried to escape.  Since these dogs were often not owned by law enforcement agencies, legend was far more important than recordkeeping. A prison-trained tracking dog was involved in a recent case in Louisiana. 

A Robbery in Natchitoches

The Tobacco Warehouse Convenience Store in Natchitoches, Louisiana, was robbed at gunpoint by two men.  Two brothers, Corey W. and Andre Oliphant, were convicted in January, 2007.  The appeal described here involves only one of the brothers, Corey, who was sentenced to forty years at hard labor without benefit of parole.  The appeal came about after the federal district court for the Western District of Louisiana, on a habeas petition, essentially directed Louisiana to allow an appeal in the case. 

The evidence at trial is summarized as follows. 

On April 23, 2005, a man with a pistol entered the Tobacco Warehouse and took approximately $700 from store employees.  The robber was described as black, with a hood pulled over his head.  He also had a piece of cloth across his chin.  At approximately the same time, a retired detention officer, living near the strip mall where the Tobacco Warehouse was located, saw a man with a hood over his head run through his yard, jump a fence, and get into the passenger side of a white, older-model Lincoln.  He noticed the molding below the bottom of a door was missing.

Two hours later a police officer saw a Lincoln Town Car run a stop sign.  The officer put on his lights but had to chase the car until it stopped.  The car was being driven by Nicholas Oliphant and was registered to Odell Oliphant, respectively another brother of the defendant and his father.  Knowing of the robbery, the officer asked Nicholas if he had a gun in the car, which he admitted he did.  The officer put Nicholas in cuffs and took a nickel-plated, snub-nosed, 22 caliber revolver with a blued cylinder from the Lincoln. 

Detention Center Tracking Dogs

Nicholas said that his brother, Corey, could verify that he had been at home all day.  Corey was brought to the police station and gave an inconsistent account of his own whereabouts earlier in the day.  A determination was made to use tracking dogs in the investigation and Corey was asked to provide a sock, with which he complied.  A tracking team was brought to the Tobacco Warehouse.  The sock was given to Officer Roy Gallien, a dog handler assigned to a nearby detention center. 

Regarding the dogs, the Louisiana Court of Appeals states:

“According to Officer Gallien, the Detention Center has six tracking dogs including ‘Bo’ and ‘Trusty,’ the dogs used in this search, as well as a number of puppies in training.  He testified that ‘the mamma dog’ had come from Angola State Prison and that she had been bred to dogs from two other correctional facilities around the state.  The dogs are not certified in any capacity, and all of their tracking expertise has arisen from use at the Detention Center.  While Officer Gallien testified concerning at least two situations where the bloodhounds were useful in a search, he provided no information concerning the expertise of anyone involved in the training, including himself. Additionally, he acknowledged that the Detention Center keeps no records concerning the dogs’ use.” 

Officer Gallien also indicated that the dogs were trained by trustees of the Detention Center. 

At the Tobacco Warehouse, Officer Gallien let Bo and Trusty sniff the sock from Corey Oliphant at about 7:15, five hours after the robbery.  The dogs tracked separately “along a route similar to what” Officer Gallien would later learn was described by the retired detention officer.  In a later part of the discussion, however, the court states that the dogs “neither tracked the exact same trail and both terminated their tracking efforts at different locations.”  It is not detailed how far apart these two tracking endpoints were. 

Corey Oliphant was arrested for armed robbery.  The Lincoln was searched, producing two items made of panty-hose or stocking-type material. Searches of the car and the house, however, produced no clothing resembling that worn by the robber, and no money that might have been taken from the Tobacco Warehouse.  Witnesses did not pick pictures of Nicholas or Corey Oliphant from a photographic lineup.  One witness, pressed to pick the photograph closest to the robber, picked someone other than the brothers.  The retired detention officer did not identify anyone.  Nor did anyone identify the gun found in the Lincoln as the weapon used in the robbery. 

Appellate Court’s Consideration of Tracking Evidence

The defendant made five assignments of error, one of which was the admission of the bloodhound testimony.  The appellate court noted that there was no evidence of certification of the two dogs but added:

“[T]he only evidence of training was Officer Gallien's testimony to the effect that much of the dogs’ training was accomplished by inmates at the Detention Center. Officer Gallien was not offered as an expert in the handling of bloodhounds, and the record contains no evidence of his training or the training of anyone else associated with the dogs. While Officer Gallien did testify to incidences of successful use of the bloodhounds, he acknowledged that no records were kept concerning the success or failure rate of operations involving the bloodhounds. When the defendant objected to Officer Gallien's testimony and lack of expertise and documentation, the trial court overruled the objection, noting that the objection would go to the weight of the evidence instead of its admissibility.”

The appellate court referred to the admission of bloodhound evidence as “an uncommon occurrence,” in contrast to narcotics detection dog evidence.  While this is true, it perhaps overlooks the fact that the earliest criminal cases where dogs were part of the investigation, going back to the nineteenth century, involved tracking dogs.  The court noted that where tracking dogs have been used, issues with regard to them have not often been raised on appeal.  This is also true, and understandable.  As with cadaver dogs, the discovery of a body often makes the question of how it was discovered irrelevant.  If, say, a gun from a robbery is found by a dog along the path the robber used to flee the scene of the crime, there are commonly other ways to connect the gun with the robber.  

The court then reviewed older Louisiana case law regarding bloodhounds, but found the best statement of a proper foundation for bloodhound evidence in a 1980 Tennessee case, Tennessee v. Barger, 612 S.W.2d 485 (Tenn.Crim.App. 1980), which stated that the handler had to be available for examination and the dog must:
  1. Be a purebred and of a type characterized by acuteness of scent and power of discrimination.
  2. Be accustomed and trained to track human (as opposed to animal) scents.
  3. Be shown by experience in actual cases to be reliable in tracking.
  4. Have been placed on the trail at a spot where the suspect was known to have been or on a track which circumstances indicate he made.
  5. Have been placed on the trail within a period of efficiency, i.e., before a rainstorm or lengthy passage of time.
Applying these factors to the case before it, the Louisiana Court of Appeals said that “there is insufficient evidence to establish the qualifications of the bloodhounds used to track the defendant’s exit from the Tobacco Warehouse.”  The court emphasized the lack of certification, and aside from a few examples of success with the dogs, noted that Officer Gallien “could not assert any degree of overall tracking reliability because of a complete lack of records.” 

In any case, the appellate court concluded that “the trial court erred in allowing the bloodhound evidence to be introduced to the jury.”

The court might have also noted research indicating that tracking dogs are less able to distinguish the scents of people closely related than of strangers.  The fact that a number of brothers and a father were involved raises the possibility that the dog might have been tracking someone other than Corey. The court did consider that the tracking, which occurred five hours after the crime, might not have been in the dog’s period of efficiency.  Many dogs would be considered efficient up to 24 hours, however, or even beyond.  (For a discussion of the five elements listed here for admission of tracking evidence and their evolution over more than a century, see Police and Military Dogs, Chapters 3 and 5. Some of those elements were considered by courts during the early stages of case law on narcotics detection dogs.  Thus, some courts considered whether drug dogs, like tracking dogs, had to be purebred.  That requirement was put aside more quickly in drug dog jurisprudence, yet still receives mention in tracking dog cases.)

Certification of Tracking Dogs

The appellate court emphasized that the dogs were not certified in any capacity, that there was “no evidence of certification of the two dogs involved in the tracking,” and that there was “a lack of Louisiana jurisprudence on the subject of bloodhound certification.”  This, the court felt, was to be contrasted with the importance of certification for drug-detection dogs, for which the court cited numerous state and federal cases, including the Supreme Court’s decision in U.S. v. Place, 462 U.S. 696 (1983).  (There was no reference to the more recent decision in Florida v. Harris.)

Although the court felt the lack of certification was important, it apparently would not have excluded the bloodhound evidence had the five elements of Barger been satisfied.  Those elements do not mention certification.  Two of the five elements specifically relate to the facts of any case before a court—where and when the dog was placed on the trail.  The other three relate to the dog and its background—its breed (that it be purebred), that it was “accustomed and trained to track humans,” and it be “shown by experience in actual cases to be reliable in tracking.”  Thus, tracking cases often depend more on a dog’s actual production in the field than any certification.  Why this is so—and that it should be so—is worth additional analysis. 

Complexity of Tracking

In Florida v. Harris, 133 S.Ct. 1050 (2013), Justice Kagan compared field records to training and testing environments, stating:

“There, the designers of an assessment know where drugs are hidden and where they are not—and so where a dog should alert and where he should not. The better measure of a dog’s reliability thus comes away from the field, in controlled testing environments.”

The Justice observed that in the field it could be impossible to determine whether a dog’s alert, where no drugs were found, was genuinely false, or was rather an alert to a residual odor or an otherwise undetectable amount.  We will argue in a forthcoming law review article that training and certification environments often contain residual odors and trace amounts of target drugs, but for purposes of analyzing this case, and tracking in general, it is to be noted that the situation in which the dog is placed and the circumstances of the assignment are very different.

A narcotics detection dog, when deployed to sniff a vehicle or other location, produces one of three results: no alert, interest without an alert, or an alert.  For the most part, this is a binary analysis, alert or no alert.  The Supreme Court, in Florida v. Harris, said that field records “in most cases have relatively limited import,” adding that “[e]rrors may abound in such records.”  It is important to understand that, for any court analyzing a tracking case, this holding should not apply to tracking situations, where the dog’s choices cannot be described as binary.  In fact, the dog’s potential actions can cover a broad set of patterns, some of which are indicated in the following table. 

Where tracking begins:
Dog’s actions:
Evidentiary significance:
Scene of crime
No trail found
None or minimal

Trail followed but soon lost
May indicate direction perpetrator took on leaving scene

Trail followed leading to location where perpetrator may have entered vehicle and driven off
May be useful if evidence connects suspect with location or vehicle  

Dog finds item connected with the crime
Significant in verifying path perpetrator took after crime; item may have independent value

Dog leads to house or building perpetrator may have entered
May lead to warrant for search

Dog leads to individual who is potential perpetrator
Sometimes admitted as identification evidence (but see  Curran et al. finding that tracking may be accurate without identification at end of trail being accurate)
Dog loses trail but then resumes trail, perhaps even after handler has discontinued search
May excluded under some state requirements that tracking be continuous

Dog loses field trail but then is encouraged to resume work at entrance to police station, leading to suspect already under arrest
Sometimes admitted as station identification (improperly in our opinion)
Location where perpetrator or suspect was seen
Dog leads back to scene of crime
May be admitted concerning path perpetrator took after crime (a reverse track), though may also indicate perpetrator returned to scene of crime

It is evident that many of these actions are far from two-choice situations such as are faced by drug dogs, that a dog following a trail is making countless assessments of the source and direction of an odor, sometimes producing significant evidence that can stand in its own right.  This is not equivalent to the possibility of a dog alerting to residual odor in a narcotics case.  Finding items associated with a crime, such as a weapon used in the commission of the crime or items taken from victims of the crime, should obviously not be evidence excluded merely because the dog involved was not certified. (Finding such items may also occur during an article search.)

Further, tracking in the field is probably more controlled, in a scientific sense, than a training or certification test environment.  In a typical field deployment, the handler does not know at the beginning of the trail which way the dog will go.  Nor does he or she know at any point along the trail when the dog will change course.  It is possible that the handler in a training or certification situation will have some idea of these matters.  The dog may be tracking in an area where other dogs have tracked before.  The handler may have seen the instructor or tester place objects with the scent the dog is going to pursue.  A field assignment is, thus, often much more of a double-blind situation than a testing or certification course.  Consequently, field records of a tracking dog can be useful in assessing the dog’s reliability.

Also, because the tracking situation is not binary, there has seldom been an argument to correlate the results of tracking dogs to exclude those dogs whose deployments do not produce evidence.  A drug dog that alerts more than others in a department may be suspected of being cued, and the Supreme Court in Harris may have wanted to avoid having full-blown trials of dogs on this basis. Tracking situations are too diverse for such a simplistic analysis and there is no need to analogize tracking evidence to drug dog evidence on the issue of certification. 


The Supreme Court’s decision in Harris should not become a means of excluding valid field evidence in every type of police dog work.  Even less should it become a reason for not keeping complete field records, or for destroying them before they may have to be made available to defense counsel. 

Several months ago we analyzed a currency forfeiture action in which we discussed recent research on quantification of currency contamination by cocaine. Certain levels of currency contamination are expected on U.S. bills, not from the fact that most bills are handled by criminals at one point or another, but probably from mechanical currency counters distributing cocaine residue across bills that enter the machine.  When a bill has above a certain level of contamination, however, it has a significant probability of having been associated with a drug trafficker. (See Jourdan et al., 2013.)  If a dog alerts to it, the prevailing theory is that the dog is alerting to methyl benzoate, an unstable compound that disintegrates rapidly, so the alert of the dog indicates that the currency was probably in contact with cocaine in the previous two days.  This creates some forensic formulas:

         High residue + Alert = Drug enterprise contamination within 48 hours

         High residue + No alert = Drug enterprise contamination older than several days

         Normal residue + Alert = Recent contamination, perhaps innocent as from currency counter

These formulas oversimplify the possibilities, but do indicate why this kind of field alert evidence should be maintained, and should fit within the exception that Justice Kagan acknowledged in Harris where a “dog’s (or handler’s) history in the field … may sometimes be relevant….” 

For any court tempted to apply the training and certification logic of Harris to a tracking dog, these considerations should be taken into account before there is any knee-jerk dismissal of field evidence or a refusal to allow discovery of such evidence. The reliability of a tracking dog may be best established by field records, in contrast to the general devaluation of such records for drug dogs by the Supreme Court in Harris.  The failure to maintain field records in this case was a sufficient reason to reject the tracking evidence.  Records should be kept and even prison-trained dogs should have records kept of their deployments, though this case demonstrates that this has not yet happened in Louisiana.  The Louisiana appellate court is right to say that it should. 

Louisiana v. Oliphant, 2013 La. App. LEXIS 2386 (Ct.App. 2013)

This blog was written by John Ensminger and L.E. Papet.

Monday, December 2, 2013

Law Student Training Service Dogs Can Sue Law School for Refusing to Admit Dogs to Classes

Nicole Lara Shumate enrolled in Drake University Law School in Des Moines in 2006 and graduated three years later.  Shumate is a service and therapy dog trainer and founded a non-profit organization called Paws and Effect the same year she started law school.  It is not clear when she first tried to bring dogs in training to classes, but her complaint stated that the law school dean notified her in September 2009 that “access to law school facilities with a service dog in training would not be tolerated per the university policy.” 

Shumate brought suit in 2011, alleging that she had been denied access to classes “because she was assisted by a service dog in training.”  She also said that a professor had denied her admittance to a cultural event being held at a local church because she was accompanied by a service dog in training.  Finally, she argued that the law school directed hostility toward her and created a “poisonous learning environment.”  The trial court determined that Shumate came within the coverage of the Iowa disability statute, but held that the statute did not grant her a private right of action.  Therefore, that court granted the university’s motion to dismiss the lawsuit.  Shumate appealed. 

Iowa Disability Statute Regarding Service Dogs

Iowa Code 216C.11(2) states that a "person with a disability or person training an assistive animal has the right to be accompanied by a service dog or an assistive animal, under control," in places of public accommodation and transportation.The trial court determined that Shumate's training activities were covered by this statute. Drake University disagreed, referring to the definition of a service dog that applied in 2009, under which such a dog had to be “specially trained at a recognized training facility.”  Drake contended that the statute applicable at the time of Shumate’s attendance of law school did not intend “any and every service-dog trainer to be a member of the class of persons protected" by the statute. Presumably, Shumate’s Paws and Effect qualified as a “recognized training facility,” though the issue received no analysis in the appellate decision.  In 2011, the reference to training in the statute was revised to state that a service dog “means a dog specially trained to assist a person with a disability….” The university also noted that the title of Chapter 216C is “Rights of Persons with Disabilities,” indicating a legislative intent only to protect persons with disabilities, not trainers of service dogs without disabilities. 

The appellate court agreed with the trial court that Shumate fell within the class of persons protected by the statute, and added that “[e]nsuring access to public places and accommodations for persons training service dogs will increase the availability of skilled dogs for disabled persons, who will then be better equipped to participate in the ‘social and economic life’ of the community.”  The court elaborated that “[e]nsuring that service dog trainers have full access to places open to the public, and thereby creating a pool of well-trained dogs to assist disabled persons in navigating public facilities, advances the stated aim of chapter 216C.” 

Private Right of Action

The fact that the statute applied to Shumate as a trainer of service dogs was not the only hurdle she had to overcome.  She also had to demonstrate that she had a private right of action under the statutes cited.  It could, after all, be the case that only a district attorney or other official could bring a criminal action under the statute.  The trial court had, in fact, concluded that a simple misdemeanor remedy “communicated the legislature’s exclusion of a private suit for damages.”  

The Iowa Court of Appeals observed that the statutory right of “a person training a service dog to be accompanied by the dog at certain public facilities and places of public accommodation … is more than a general statement of policy; instead it sets out concrete requirements to allow access to trainers accompanied by service dogs.”  The appellate court concluded that the trial court “erred in finding the inclusion of a simple misdemeanor penalty ... revealed a legislative intent to deny a private cause of action,”  adding:

“The overarching purpose of chapter 216C is to guarantee persons with disabilities greater access to public facilities and wider participation in the social and business community, not to craft a criminal offense to punish those who exclude persons training service dogs from public places.”

The court stated that it “would be inconsistent with the underlying purpose of the chapter to pair these robust rights with the meager remedy of a simple misdemeanor prosecution.”  (The maximum penalty if the university were convicted of a misdemeanor would have been a fine of $625.)  The court continued that it “follows that allowing a service dog trainer to enforce this policy by bringing a private right of action, if denied access while accompanied by a service dog, is consistent with the underlying purpose of the statute.”

The Court of Appeals reversed the dismissal of Shumate’s petition and remanded for further proceedings.


The case is not over.  Shumate will have to support her claims for monetary damages and the university might still make a fundamental-alteration argument with respect to the presence of dogs in training in a law school environment.  This might be difficult, however, given that Drake appears not to have given Shumate much, if any, opportunity to have a dog in a class and demonstrate that it would not interfere with the class or other students. Had she brought one in, and had it been unruly and distracting, then the university would have had other arguments, but this is not stated in the facts as having happened.  If Shumate had been going to medical school, the sanitary requirements of certain environments would have allowed the university to exclude her dogs from those environments.  Law schools, however, are just classrooms with desks and a blackboard. 

Although I think the case is correctly decided, I have to say that when I was going to law school I would not have considered bringing a dog I was training with me.  I began law school at a time when cases were still recited.  A student called on to explain a case had to stand up, summarize the facts of the case and justify a position that it was correctly or incorrectly decided, then withstand sometimes half an hour of debate with a professor over the issues. (I once worked with a lawyer who had been a classmate of John Jay Osborn, author of The Paper Chase.  He assured me that he was in the same class as Osborn when the Harvard law prof Osborn fictionalized as Charles W. Kingsfield gave a dime to a student after a poor recitation and actually said, 'Here’s a dime.  Go call your mother and tell her you’re not going to be a lawyer.') I would not have wanted to have a dog at my feet, and thinking back on it, would not have wanted to risk the dog becoming restless or sensing my anxiety.  Nevertheless, that was a long time ago and law school is apparently somewhat more benign these days. 

Shumate v. Drake University, 2013 Iowa App. LEXIS 1152 (Ct.App. 2013)

Additional Note.  I received an email from a reader who pointed out that the law school dean did not notify Ms. Shumate to keep her dogs away from the school until 2009.  If she did not attempt to bring the dogs in the first two years of law school, the reader notes, she likely did not bring the dogs to classes where the severe structure I describe would have applied.  This is true.  Third year classes are often rather specialized, sometimes seminars, where a degree of informality is common.  If there are any further orders or opinions in the case, it will be interesting to learn more about when Shumate began trying to bring the dogs to classes.  We might also learn about the dogs themselves.  Were they nearly done with training, or were they only beginning to be trained?  This raises interesting questions.  Could a fundamental-alteration argument apply to dogs at the beginning of training but not to dogs about to go to work?  Also, could a fundamental-alteration argument apply to first-year Torts but not to a third-year seminar on the Law of Urban Planning?

Tuesday, November 26, 2013

Do Dogs Detect Hypoglycemia? Two Studies Say Yes, but a Third Raises Serious Doubts

Three UK scientists, one of which is the CEO of a dog training organization that specializes in medical detection dogs, have published a study (Rooney et al. 2013) that “points to the potential value of alert dogs, for increasing glycaemic control, client independence and consequent quality of life and even reducing the costs of long term health care.” Another preliminary study (Gonder-Frederick et al., 2013), also using self-reporting, largely confirmed the results of the first study.  A third study (Dehlinger et al., 2013), however, found that trained hypoglycemia alert dogs, when faced with swabs taken from patients during hypoglycemic periods and swabs taken during normal glycemic level periods, could not distinguish them at a level greater than chance.  It will be important for future research, and for the credibility of this kind of service dog, to determine how such disparate results can be reconciled. 

The UK Study

Summarizing prior research, Rooney et al. noted that “studies relied on owners accurately recalling past events,” meaning that “the frequency with which dogs respond may be over-reported.”  They also note that previous studies of dogs have concentrated on hypoglycemic episodes exclusively, whereas their study also examined hyperglycemia.  The subjects in this study had Type 1 diabetes.

Medical Detection Dogs, the charity of one of the authors, has trained over 20 dogs in hypoglycemia alerting. This and other charities have used trained alerting behaviors that “include licking, pawing, jumping, staring, vocalizing and even fetching a blood testing kit” when an owner’s blood sugar level falls outside a target range, usually 5-15 nm/l. (Alerting by fetching a blood testing kit is a specific set of actions that is not likely to be accidental, but it must be wondered if owners might sometimes confuse some of the other actions with non-alerting activities of a dog.  It is to be hoped that the authors will follow with an article about the training methods used in this study.)  This study sought to assess claims that using such dogs facilitates tightened glycemic control, reduces hypoglycemic episodes, nocturnal lows, and calls for paramedic assistance.   

The 16 subjects completing the study were clients of Medical Detection Dogs with trained and certified or “advanced trainee dogs,” the latter being deemed to alert sufficiently accurately to participate in the study despite a lack of certification.   Subjects had lived with a hypoglycemia alert dog as short as four months and as long as seven years.  The subjects provided detailed information about how having an alert dog had changed their lives, including the estimated frequencies of low blood sugar pre-dog and with the dog, of episodes of losing consciousness, and of paramedic calls.  All subjects reported a decrease in at least one of these categories after obtaining a trained dog.  Eight people who reported having episodes of unconsciousness before getting a dog said they did not have such episodes after getting one.  Three people reported having made paramedic calls before getting a dog but not after.  Almost all subjects (15) trusted their dogs to alert to low blood sugar levels, while 13 trusted them to alert to high blood sugar levels. The scientists explain this discrepancy from the fact that alerting to high blood sugar “is a secondary task, trained subsequent to a strong alert to low blood sugar.” 

In the second phase of the study, subjects were asked to record their dog’s alerting behavior and to provide blood test results.  The study found that blood tests for eight of ten subjects showed that a sample taken after a dog’s alert was significantly more likely to be out of target range than was a routine sample.  One dog was apparently alerting at random.  The study states that for “the best performing dog, the odds of an alert being when bloods were out of range were 10,000 times higher than that of routine tests.”  Eight subjects who recorded nocturnal lows pre-dog had fewer nocturnal lows post-dog, though two had an increase post-dog.

The authors of the study state their results with some hedging on the fact that much of their data depends on self-reporting by subjects:

“The population, overall, reported reduced unconscious episodes and paramedic call outs, which if accurate, is of great importance since not only does it represent increase health and safety of the client, but also potentially significant reduced costs in health care.”    They also note that “for 80% of the clients providing sufficient data, when their dog was recorded to perform an alerting behaviour their blood was significantly more likely to be out of target range than it was during routine samples. In addition, comparison of owner’s routine test records from before and after obtaining their dog, showed highly significant overall change: all but one client being more likely to be within target range post-dog; five out of nine clients experienced a significantly reduced incidence of low blood sugars, and three of the remaining four showed a significant reduction in high blood sugars, suggesting improved glycaemic control in most clients. The two clients who showed no significant increase in percentage within target (1 and 5), had dogs which were unqualified and the clients reported to be experiencing training problems, which were subsequently resolved.” 

As to what the dogs are actually alerting to, these scientists argue that odor cues are the most plausible explanation, particularly given that when this occurs when owners are asleep, behavioral cues would presumably be few, “although changes in breathing rate may occur.”  Also, some owners report the dogs alerting when they are in another room.  Thus, it “is likely that dogs detect changes in the chemical composition of their owners’ sweat, or breath (including products of ketosis)….” 

The Virginia Survey
A short paper appearing in Diabetes Care, Gonder-Frederick et al. also gathered data from persons with Type 1 diabetes.  The patients had received diabetic alert dogs from Service Dogs by Warren Retrievers, Inc., located in Culpeper, Virginia.  The survey asked how often respondents experienced hypoglycemia with no corresponding alert from their service dog.  More than a third (36.1%) reported no such occurrences, 27.8% reported fewer than one event per week, and 36.1% reported more than one per week. Respondents reported significant decreases of severe and moderate hypoglycemia since getting a dog, though detailed statistics were not included in the one-page summary.  Subjects reported decreased worry about hypo- and hyperglycemia, and increased participation in physical activities.  The authors of the study conclude that their preliminary results justify additional research. 

The Oregon Study

In a study that did not use self-reporting, Dehlinger et al., subjects rubbed sterile cotton swab samples by rubbing them on the skin of both arms during hypoglycemic and normal glycemic periods.  (The UK study also indicated that the dogs were “increasingly” trained “using remote odour samples collected from clients during times of hypoglycaemia” before the dog and owner were introduced.) The three dogs used in the study had been trained to press a bell after sniffing a container with a hypoglycemic swab.  The dogs were trained by Dogs Assisting Diabetics Foundation of Forest Grove, Oregon.  The owners of the dogs, and their trainer, believed the dogs were consistently able to detect hypoglycemia.  Each dog was tested with 24 samples by being presented with a sample from 30 to 45 seconds.  The overall results for each dog, and combined, are contained in the following table.

Dog 1
Dog 2
Dog 3
Percent correct, each
Percent correct, all
Sensitivity, each
Sensitivity, all
Specificity, each
Specificity, all

The researchers did not provide an explanation as to why dogs trained to alert to hypoglycemic swabs could not do so in their experimental setting.  The researchers concluded that “trained dogs were largely unable to identify skin swabs obtained from hypoglycemic T1D subjects.” They indicate that future studies should factor in behavioral effects, and should perhaps look at swabs taken only from the usual human companions of the dogs. 

I am particularly concerned about this study because a researcher with whom I occasionally work told me that he met a detection dog trainer at a diabetes conference.  Concerned that her description of how the dogs worked allowed for a Clever Hans effect, he asked to use three dogs for a quick double-blind study.  The dogs did not perform better than chance. 

How Can the Inconsistencies Be Explained? 

There are a number of ways that the inconsistencies of the studies might be explained. Chemical changes might be complex, and vary in the sweat of different owners.  Dogs trained from sweat swabs from the skin of multiple owners might, once deployed with a single owner, display different levels of recognition of hypoglycemia.  If dogs primarily or even partially recognize low or high blood sugar from behavioral changes in their owners, this could also explain some inconsistencies.  If it is ultimately verified that dogs recognize changes in blood sugar changes when their owners are asleep, behavioral recognition might be reduced to detection of changes in breathing patterns.  It is also possible that if dogs recognize changes in blood sugar from a mixture of chemical and behavioral changes, a study only looking only at chemical changes, as is true of the third paper discussed above, will not produce good results. 

There were many more dogs in the first two studies than in the third, which had only three.  It could be that a larger number of dogs in the third study would have produced more positive results.  As noted above, the researchers did not explain why dogs trained to recognize hypoglycemic swabs did not do so effectively in their study.  The research used double-blind investigators.  Were the dogs trained in an environment where cueing was possible so that in an experimental environment where it was not the results were not significant? Was there a Clever Hans effect because the dogs were responding to the patients’ behavior?  Were other controls missing from the training environment, meaning the dogs were not really trained at the level the researchers supposed?  Were the methods of collecting sweat in training and in the experiment really identical?    

Self-reporting may be more flawed than is acknowledged in the first two studies. Patients may be seeing what they want to see, or the companionship of the dogs may make patients more attentive to their own care.  The blood samples collected by subjects in the first study after their dogs alerted were significantly more likely to be out of the target range than a routine sample.  If, however, the owners recognize the change in themselves, could they be unconsciously cueing their dogs to alert, then taking the samples.  If this turns out to be the case, are the dogs, presently recognized as service dogs, really emotional support animals?  Since they are trained to perform behaviors related to the disability of their owners, they would arguably still be service dogs, but if those behaviors do not in fact correlate with the aspect of the disability the dogs are supposedly trained to react to, is the training still related to the disability?  That is a legal question that, my guess is, courts will not look forward to considering soon.


Hypoglycemia alert studies bear a resemblance to seizure alert studies in that most results to date have involved self-reporting.  As I noted in the chapter on this subject in Service and Therapy Dogs in American Society, one study that videotaped two patients with dogs in an epilepsy care unit (Ortiz and Liporace, 2005) found that seizure dogs were poor in alerting before a seizure and concluded that seizure dogs “were not as effective as previously thought in predicting seizure activity.”  These authors acknowledged the small size of their sample. Another study (Krauss, Choi, and Lesser, 2007) found that seizure-alert dogs were effective in detecting psychogenic nonepileptic seizures (PNES) but not necessarily in detecting epileptic seizures. The authors stated the cases they analyzed "show that patients with abnormal illness behaviors may seek service animals for support." 

Scientific discoveries often begin with anecdotal accounts, such as the initial reports of dogs that seemed to recognize that dark patches of skin on their owners were somehow disturbing, followed by the discovery that the spots were melanomas.  This led to the phenomenon of cancer sniffers.  Rigorous studies on cancer detection by dogs, however, have led to high levels of specificity and sensitivity of 80% or more, not the anemic 50% shown here.  For scientists to be persuaded that dogs can reliably detect hypoglycemia, there will have to be something more than has been demonstrated by survey studies, no matter how sophisticated, since these studies are inevitably subjective, sometimes little more than a distillation of multiple anecdotal reports.  

It is important that hypoglycemia alerting be verified in strict double-blind settings, and it can be expected that such conflicting results as discussed here, and the ultimately positive benefits if alerting is verified to actually occur, will encourage additional research and open the spigot for funding such research.  The law should sit on the sidelines for a time, as long as dogs that are claimed to have blood sugar level detection abilities are also trained well enough not to be a distraction to other patrons or passengers in public places and transportation.  Nevertheless, even here there should be an expectation that this type of alerting can eventually be supported by highly controlled scientific results. 

This blog was written by John Ensminger and L.E. Papet. Thanks to Dr. Tadeusz Jezierski for comments. 


Dehlinger, K., Tarnowski, K., House, J.L., Los, E., Hanavan, K., Bustamante, B., Ahmann, A.J., and Ward, W.K. (2013).  Can Trained Dogs Detect a Hypoglycemic Scent in Patients with Type 1 Diabetes?  Diabetes Care, 36, e-98-9.

Gonder-Frederick, L., Rice, P., Warren, D., Vajda, K., and Shepard, J. (2013). Diabetic Alert Dogs: A Preliminary Survey of Current Users. Diabetes Care, 36, e47.

Krauss, G.L., Choi, J.S., and Lesser, R.P. (2007).  Pseudoseizure Dogs. Neurology 68(4), 308-9.

Ortiz, R., and Liporace, J. (2005).  “Seizure-alert dogs”: Observations from an Inpatient Video/EEC Unit.” Epilepsy and Behavior, 6(4), 620-622.

Rooney, N.J., Morant, S., and Guest, C. (August 2013). Investigation into the Value of Trained Glycaemia Alert Dogs to Clients with Type 1 Diabetes.  PLOS/One 8(8), 369921. 

Monday, November 25, 2013

When a Therapy Dog Bites

A handler who belongs to a national therapy dog organization, as I do, is required to certify annually that the dog has not bitten anyone or shown overt aggression since the previous renewal of membership.  This requirement is not limited to incidents that happen during visitations.  A recent case from New York involved a therapy dog that bit a guest at a party in the home of his owner.  The certifying organization was not informed of the bite (until I sent them an email asking for comment), and the dog's certification continued for two years after the incident.  Should the dog have been allowed to continue a visitation schedule? I look at the issues of this case in a commentary posted on the website of the Animal Legal and Historical Center.

Saturday, November 16, 2013

Psychiatrist’s Letter Proves Crucial in Patient's Dispute with Landlord over Dog

Dr. J.L. Thomas and I wrote an article for psychological and medical professionals regarding letters that such professionals are asked to write on behalf of patients with service and support animals.  In the article, which appeared in the Journal of Forensic Psychology Practice, we analyzed letters that were influential in legal cases where patients sued to gain access to public accommodations, transportation, or housing.  We also analyzed letters that had the opposite effect, either not helping patients or actually harming their cases.  A recent case from a federal district court in California involves a letter from a psychiatrist that was the primary evidence that persuaded the judge to grant summary judgment for the patient who had sued the landlords for failing to grant her a reasonable accommodation to live with a dog that, according to the psychiatrist, was “of much benefit to her mental state and necessary for her continued stabilization.” 

Difficulty with a Landlord

Sharon Smith suffers from various mental disabilities, with symptoms that include depression, frequent bouts of crying, and anxiety.  Her psychiatrist, Dr. David L. Friedman, concluded that she was “temporarily totally disabled,” and diagnosed her as having adjustment disorder, pain disorder, and insomnia.  Smith herself states that her mental disabilities inhibit her ability to take care of herself, get out of bed, interact with others, and remain focused.  She also suffers from injuries to both wrists, for which she has received surgery but has not fully recovered.

Smith has lived with a companion dog, Layla, a ten-pound terrier.  Smith asserts that the dog helps to alleviate the symptoms of her mental disabilities, and stated in a declaration to the federal district court for the Central District of California that Layla “helps me keep a regular routine of caring for myself, motivates me to get out bed, clean, maintain relationships with friends and family, and to exercise.” 

In June 2012, Smith moved into an apartment rented by Harold and Zelma Powdrill before seeing, signing, or reviewing a lease agreement.  She informed Philip Powdrill, a son of the owners, that she would be living with a dog, which she told him was a companion animal necessary to address her disabilities.  Philip sent a text message to Smith asking her how the dog was doing in its new home. 

On June 30, Valerie Powdrill, the daughter of the owners, gave Smith a copy of the rental agreement to review and sign.  The agreement included a no-pets clause that stated:  “No dog, cat, bird, or other domestic pet or animal of any kind may be kept on or about the premises without LANDLORD’s written consent.”  Smith signed the lease but did not initial the page with the no-pet provision. 

According to the federal district court for the Central District of California:

“Uncomfortable with representations by Philip Powdrill that she could keep the dog so long as she kept it on the ‘down low,’ … , on or about July 12, 2012 Plaintiff sent a handwritten letter to Defendants requesting an exception to the no-pet policy…. In the letter, Plaintiff introduced herself as a new tenant and stated that she has undergone surgery to both her hands due to workplace injuries, receives disability benefits, and is currently attending physical and mental therapy…. Plaintiff stated that she was unaware of the no-pet policy when she moved in and requested an accommodation to allow her to keep the dog because it had been deemed a necessary form of emotional support by her doctor…. She described the dog as ‘well trained, doesn't bark, [and] completely house broken.’”

The Psychiatrist’s Letter

To her own letter, Smith attached a letter from her psychiatrist, Dr. Friedman, stating:

Please be advised that I have been treating Ms. Smith since April 2012. As part of her psychiatric difficulty she suffers from a severe Adjustment Disorder, Pain Disorder, and Insomnia. Due to Ms. Smith's psychiatric condition, having a companion animal would be of much benefit to her mental state and necessary for her continued stabilization. I believe, Ms. Smith should be allowed to have such animal at her place of residence. Should you have any questions please do not hesitate to contact this office.”

Zelma Powdrill replied to Smith’s letter on July 16, 2012, denying the request for an accommodation.  The letter said that Smith had given differing explanations as to who owned the dog and whether it would be living with her, adding:  "Your letter dated July 12, 2012, asking us to allow you and the dog to stay, indicates you are in possession of a dog in the apartment…. Our lease clearly states no pets are allowed, therefore we have enclosed a NOTICE TO PERFORM CONDITIONS AND COVENANTS OR QUIT."  The notice was attached, stating that Smith had three days to comply or leave the premises.

On July 24, 2012, a former case analyst at the Housing Rights Center, Gabriela Garcia, called and spoke to Zelma Powdrill, telling her that Smith was a person with mental disabilities and requires the use of a companion animal to alleviate the symptoms of her disabilities.  Zelma insisted that she would not allow Smith to keep the companion dog in the unit, saying that it would result in extra costs to renovate the apartment, that dogs are meant to be kept outside, and that she wanted Smith out of the unit.  Garcia sent a letter to Zelma concerning their conversation and confirming the Powdrills’ refusal to grant the requested accommodation.

Smith vacated the apartment on March 7, 2013. 

Tenant Files Lawsuit

Smith filed suit under the Fair Housing Amendments Act, the California Fair Employment and Housing Act, the California Disabled Persons Act, and on other grounds, asserting that the Powdrills’ actions had caused her emotional distress, including stress, heightened depression, increased anxiety, fear of retaliation and eviction, and humiliation.  She sought compensatory and punitive damages, as well as attorney’s fees.  The federal district court granted summary judgment to Smith under the three Acts, meaning that the primary issue left to litigate will be the amount of damages for which the Powdrills will be liable. 


As Dr. Thomas and I note in our article, it should not be necessary to give a diagnosis in a letter but, particularly in housing situations, the inclusion of a diagnosis has often been persuasive to courts and appears to have been so here. The letter was obviously written by the doctor himself, as opposed to reading as if downloaded from a website or written by the patient for the doctor to sign.  It avoids any overly broad statement about what benefit the dog will provide—that is, no cure is claimed.  Rather, it simply states that “a companion animal would be of much benefit to her mental state and necessary for her continued stabilization.”  Finally, the psychiatrist indicates his willingness to talk with the landlords if they should wish.  It was the refusal of the landlords to engage in any kind of dialogue with the tenant, to find out anything more about what the dog meant to her, to even consider that it might not just be a pet, that doomed their case. If Dr. Thomas and I ever revise our article, this decision will be included.