ProPublica reporter Brett Murphy published his first article in a series of investigative reporting about a controversial method being used by some law enforcement officers to determine whether a 911 caller is guilty or innocent. NC homicide investigators were trained at a NC Homicide Investigators Association Conference by the method’s creator, Tracy Harpster. The method instructs investigators to look for a series of indicators of guilt or innocence, including things like the amount of detail provided, whether there is an immediate plea for help, whether there are pauses or repetition, and use of the expression “huh?”.
The method is based on Harpster’s study of 911 calls. Scientists at the FBI’s Behavioral Analysis Unit tried to replicate Harpster’s research in two separate studies in 2021 and 2022 cited in the ProPublica article (available here and here). However, the studies found that Harpster’s results couldn’t be replicated and that previously-defined indicators of deception in 911 calls may be unreliable.
While I’m not aware of testimony by Harpster being offered as evidence in any NC case, the ProPublica investigation found examples of Harpster’s training shaping the course of investigations in other states, with or without Harpster’s direct involvement in the case. So there are implications to consider even where there is no disclosure of expert testimony about the method. Counsel should be aware that law enforcement could try to use Harpster’s methods to establish probable cause to arrest a suspect. Counsel should consider challenging probable cause where it is based on this type of 911 call analysis. At trial, it seems clear that testimony about this method would not survive a 702/Daubert challenge. However, counsel should guard against officers trained in Harpster’s method testifying about indicators of guilt in a 911 call without mention of Harpster’s method. This could be an effort to introduce this testimony without it being subjected to a 702 challenge. Testimony about “indicators of guilt” in a 911 call should be challenged under Rule 702 where the testimony is based on specialized knowledge, training, education or experience. Additionally, counsel should also guard against a prosecutor arguing in closing that there were indicators of guilt in the 911 call.
To determine whether this method was used in a particular case, counsel should look out for use of the 911 COPS (Considering Offender Probability in Statements) Scale which is a checklist that guides officers in employing Harpster’s method. However, it is important to keep in mind that if local investigators are trained in Harpster’s method, the method might be utilized without there being clear evidence of its use.
If you think this method was used in one of your NC cases or you’d like more information, please contact me at Sarah.R.Olson@nccourts.org for a case consultation which are free of charge in court-appointed and public defender cases.