- Testimony that a properly trained bloodhound (or any other breed of dog with an acute sense of smell) followed a trail that led to the defendant is relevant for proving the identity of the defendant as the perpetrator.
- Traditionally, the state had to lay a proper foundation by showing that the dog has: (i) an appropriate pedigree; (ii) proper training; (iii) experience; and (iv) proven reliability in the case at hand, but more recent cases have held that a formal pedigree is not essential if the other three foundation factors are all present.
- The state must also show the relevance of the tracking by connecting the beginning of the trail (e.g., scene of the crime) to the end of the trail (e.g., where defendant was located).
A properly trained canine and handler may be called upon to track (or “trail”) a fleeing suspect (such as a person who jumped and ran from a vehicle), or to follow a trail where the evidence indicates that the suspect may have left the scene (such as the broken rear window of a burglarized house) in order to locate the suspect. Testimony that this canine tracking led police to the defendant is relevant for the purpose of identifying the defendant as the perpetrator. See State v. Irick, 291 N.C. 480 (1977) (“Given all the circumstances, including the very late hour, we believe it highly unlikely that the track from the dining room window could have been left by anyone other than the burglar.”).
Lay testimony or expert opinion?
In some cases, evidence of canine tracking might be admissible as ordinary lay testimony about the officer’s own observations. For example, if the officer had an opportunity to see the defendant before the defendant fled the scene and the officer is only testifying that (with the assistance of a dog) he located and arrested that same defendant or found an item that he saw the defendant discard, that testimony should be admitted based on the officer's personal knowledge. See State v. Walston, 193 N.C. App. 134 (2008).
But in most cases, the prosecutor will want to qualify the witness as an expert so that he or she can give testimony interpreting the dog’s reactions, explaining the significance of “following a trail,” and ultimately giving an opinion as to why he or she believes that the person identified at the end of the trail (i.e., the defendant) is the same person the dog was tracking at the beginning of the trail (i.e., the perpetrator who left the scene of the crime).
When there is an objection to the introduction of evidence identifying the defendant as a result of being tracked or trailed by a dog, the state must lay a proper foundation for the dog’s reliability in tracking or trailing a scent by proving the factors below by a preponderance of the evidence. See State v. Taylor, 337 N.C. 597 (1994) (“We have held that evidence of bloodhounds' actions is admissible when it is shown: (1) that they are of pure blood, and of a stock characterized by acuteness of scent and power of discrimination; (2) that they possess these qualities, and have been accustomed and trained to pursue the human track; (3) that they have been found by experience reliable in such pursuit; (4) and that in the particular case they were put on the trail of the guilty party, which was pursued and followed under such circumstances and in such way as to afford substantial assurance, or permit a reasonable inference, of identification.”).
Older cases on dog tracking placed an emphasis on whether the dog was a “pure” bloodhound or related breed. See State v. Porter, 303 N.C. 680 (1981) (handler’s testimony that dog was pureblood, trained to follow human scent, and had done so successfully at least sixty times was sufficient); State v. Bines, 8 N.C. App. 1 (1970) (allowing testimony about tracking by a dog that was a “three way cross” of part bloodhound, part black and tan coon hound, and part red bone coon hound).
However, if the dog’s lineage did not establish a pure bloodhound pedigree, the dog’s owner or handler could provide an alternative pedigree through evidence of the dog’s performance. In other words, the dog “pedigrees itself” based on past performance. See State v. Rowland, 263 N.C. 353 (1965) (“In practice, if the dog has been identified as a bloodhound, it has been the conduct of the hound and other attendant circumstances, rather than the dog's family tree, which have determined the admissibility of his evidence”); accord, State v. Taylor, 337 N.C. 597 (1994) (“In any event, we have concluded that a dog identified as a bloodhound has “pedigreed himself” if he trails human scent”).
More recent cases have gone even further and held that the dog's breed is no longer a significant factor, as long as the other three foundational requirements discussed below (training, proven tracking ability, and use of reliable tracking procedures). See State v. Barrett, 266 N.C. App. 101 (2019) (affirming admission of tracking evidence even though breed of dog was never established, noting that the four-factor test “has been modified over time” and “courts have recently placed less emphasis on the breed of the dog and placed more emphasis on the dog’s ability and training”); State v. Green, 76 N.C. App. 642 (1985) (court cited several cases that indicate a “decreasing emphasis on the requirement that the tracking dog be a pure blood bloodhound,” and found that training and experience sufficiently qualified two dogs, a Doberman and a Rottweiler: “evidence of tracking by a dog is admissible where the dog is not a bloodhound as long as the final three foundation requirements are satisfied”).
The state must show that the dog was trained to pursue the human track, and accustomed to performing this task. See State v. Davis, 54 N.C. App. 596 (1981) (evidence was admissible where dog was properly trained and reliable, even though other dogs at the same training facility had higher success rates); State v. Irick, 291 N.C. 480 (1977) (challenges to a bloodhound’s formal training may be overcome by showing through past experience that the dog is reliable).
The state must show that the dog has a proven ability in tracking - that is, that the dog has been found by experience to be reliable in pursuit. See State v. Davis, 54 N.C. App. 596 (1981) (bloodhound evidence admissible even though dog only had a 50-65% success rate, while other dogs at the facility were 65-70% successful).
- Reliability of tracking defendant
Finally, the state must show that the dog was “put on the trail” of the defendant, who was pursued and followed under such circumstances and in such a way as to offer substantial assurance or to permit a reasonable inference of identification in this case.
a) Beginning of the trail:
The state must show that the dog was appropriately “put on the trail” of the defendant – that is, the state must show that the person being trailed was the same person suspected of committing the criminal offense. See State v. Irick, 291 N.C. 480 (1977) (tracking evidence admissible where dog was taken to the place where defendant was last seen and then began tracking); but see State v. Lanier, 50 N.C. App. 383 (1981) (no substantial assurance that the person trailed and located by bloodhound was actually the person who committed the crime, where there was no evidence that the person was at the place where dog was released to track alleged thieves).
b) End of the trail:
Dog tracking evidence does not have to result in a “positive identification” to be admissible. This means that the dog does not have to bark, bay or otherwise identify the defendant in some way at the end of the trail, as long as a reasonable inference of the defendant’s guilt arises from the facts. See State v. Rowland, 263 N.C. 353 (1965) (in robbery case, it was immaterial that there was no evidence offered about what dog did at end of trail, since dog led deputy to the defendant “sitting on a cache of money”); State v. Irick, 291 N.C. 480 (1977) (“To be admissible bloodhound evidence does not have to result in a positive identification. So long as a reasonable inference as to defendant's guilt arises on the facts, the evidence is for the jury.”)
c) Losing or changing the trail:
The fact that a tracking dog loses and then reacquires the trail leading to the defendant does not affect the admissibility of the evidence, as long as the defendant was pursued and followed under circumstances offering substantial assurance of identification, such as reliable evidence corroborating that the defendant was at the location indicated by the dog. See State v. Davis, 54 N.C. App. 596 (1981) (testimony that dog “followed a scent from the automobile to the service station before he was taken off the track and then found the scent in the woods by Sugar Creek Road and followed it to the defendant would place the defendant at the service station”); State v. Irick, 291 N.C. 480 (1977) (“one could reasonably infer the guilty party took a side trip beginning at the house where Snoopy became confused to the Hipp house and back before returning to the service station”).
Most of the cases cited above were decided before Rule 702 was amended in 2011 to incorporate the Daubert reliability test. However, cases decided after the Daubert amendments have continued to uphold the admissibility of dog tracking evidence, as long as a proper foundation is laid. See State v. Barrett, 266 N.C. App. 101 (2019) (based on officer's testimony regarding dog's ability, training, and behavior during the search, “[t]he State laid a proper foundation for admission into evidence the actions and results by Carlo, the tracking dog”); see also State v. Battle, 253 N.C. App. 141 (2017) (reversing conviction for insufficient evidence of constructive possession, and not directly addressing the Daubert inquiry, but implicitly upholding the admission of testimony at trial about dog tracking).
Additionally, federal trial courts have considered this issue under Daubert and have allowed expert witness testimony about dog tracking into evidence. See, e.g., U.S. v. Graham, 504 Fed. Appx. 63 (2d. Cir. 2012) (unpublished) (applying Daubert to determine admissibility of dog tracking, and finding “no error, much less manifest error, in the admission of Belmont's expert testimony as a canine handler”); U.S. v. Hornbeck, 63 Fed. Appx. 340 (9th Cir. 2003) (unpublished) (“district court did not abuse its discretion when it determined that the canine tracking evidence was relevant and not unfairly prejudicial” – testimony allowed under Daubert).