Why Multi-Perpetrator DNA Cases?

1. Lessons Learned from Multi-Perpetrator DNA CasesEdwin Grimsley, Case Analyst - The Innocence Project

2. In cases where the number of perpetrators is definitively known, DNA testing can conclusively prove a defendant’s innocence. • We can definitively know the number of perpetrators when victim(s) or witness(es) provide a clear account with a fixed number of perpetrators. • Because we know number of perpetrators, proving innocence through DNA differs from un-witnessed cases. Why Multi-Perpetrator DNA Cases?

3. Of the nearly 300 DNA exonerations, there are 22 cases where a victim or witness at the crime scene said there were multiple perpetrators involved. • These multi-perpetrator DNA cases represent 29 exonerations.

4. Lesson 1: You can prove one of the alleged perpetrators innocent even when his co-defendant/alleged co-perpetrator is included by DNA testing or claims guilt. • Lesson 2: You cannot assume that someone is not innocent just because they haven’t requested help from an Innocence Project. • Lesson 3: Multi-Perpetrator DNA cases can be broken down into a few core principles. Lessons We’ve Learned from Multi-Perpetrator DNA Cases

5. Lawrence McKinney spent 31.5 years in the Tennessee prison system for a rape he did not commit. In 2009, DNA testing excluded McKinney as one of the individuals involved in a two perpetrator rape of a single victim. Michael Yancey, who was McKinney’s co-defendant, wrote to the Innocence Project claiming innocence. The Innocence Project accepted Michael Yancey’s case in 2007. Lawrence McKinney

6. Lesson 1: You can prove one of the alleged perpetrators innocent even when his co-defendant/alleged co-perpetrator is included by DNA testing or claims guilt.

7. Background Info: Victim • 30 years old • One victim, female • Lived with boyfriend and two children in Memphis, TN • Boyfriend at work on the night of the crime • Victim was asleep in her bed

8. Two perpetrators (P1 and P2) enter V’s home around 5 am.

9. P1 and P2 demand money. V refuses. P1 sexually assaults V in her bed. V reports that P1 ejaculates.

10. P2 subsequently rapes V. V reports that P2 ejaculates.

11. Both P1 and P2 ejaculate: We’d look for two DNA profiles.

12. Victim tells Police: “I saw two assailants and both raped me.” V was brought to a hospital where a rape kit was collected.

13. Victim believed both assailants lived in her building = she identified them as “Michael” (P1) and “his friend” (P2) whom she did not know well. • Michael Yancey (P1) and Lawrence McKinney (P2), who lived in the building, were arrested within an hour of the crime. Identification/Arrest

14. Michael Yancey told us that he was not at the crime scene. Yancey named another man (not Lawrence McKinney) as the actual perpetrator. • We did not know Lawrence McKinney’s claims at the time of acceptance. McKinney claimed innocence when DNA sample was collected. • We sought to test DNA profiles of Yancey, McKinney, and the alternate perpetrator. Innocence Claims

15. Two foreign DNA profiles that excluded V would be obtained. The profiles would not match Michael Yancey, Lawrence McKinney, or the victim’s boyfriend. • Two foreign DNA profiles that excluded V would be obtained. One profile would match Lawrence McKinney and a second profile would exclude Michael Yancey and the victim’s boyfriend. • One foreign DNA profile that excluded V would be obtained. The profiles would not match Michael Yancey or Lawrence McKinney. The foreign profile would be uploaded into a DNA database and hit to somebody with no connection to Yancey or McKinney. Three scenarios to prove innocence

16. The rape kit was not located. Semen was identified on bedsheets and V’s panties. DNA mixture of at least two individuals was found on both the panties and bedsheets and these DNA profiles were consistent with each other. • Michael Yancey could not be excluded from one of the profiles and could not be proven innocent. • Lawrence McKinney was excluded from both profiles, proving his innocence. DNA test Results

17. Co-defendant Steve Thomas admitted his involvement to the police. Thomas named Mumphrey as his co-perpetrator. • Two perpetrator rape. Both perpetrators raped a single victim. Arthur Mumphrey Exoneration

18. Mumphrey, who claimed innocence, hired a local Houston attorney to pursue DNA testing. V’s rape kit and underwear were DNA tested. Two profiles were developed that matched Steve Thomas and an unknown male. • Mumphrey was excluded and subsequently exonerated.

19. Lesson 2: You cannot assume that someone is not innocent just because they haven’t requested help from an Innocence Project. Lawrence McKinney did not contact the Innocence Project or other organizations.

20. Limited knowledge of attorneys or organizations to contact because of poor jail resources • Mental Health Issues • Gave Up Fight after Incarcerated Reasons why innocent defendants/co-defendants do not contact attorneys/organizations

21. Literacy • Does Not Understand Science or Legal Process

22. Lesson 3: Multi-Perpetrator DNA cases can be broken down into a few core principles.

23. We must account for every perpetrator alleged to have participated in the crime. • Two things to look for in Multi-Perpetrator cases with a live victim/witness: • Victim or witness defines number of perpetrators. • Match each perpetrator seen to a specific profile on crime scene evidence.

25. Alternative to the traditional Multi-Perpetrator theory: • CODIS/Database hit to someone unrelated. • Match to alternate perpetrator who committed crime with another person. Scenario: Trump Card?