2026 Presentations
This presentation will focus on the behavioral analysis techniques used to assist the Westminster, CO Police Department in their 2012 investigation into the abduction of 10-year-old Jessica Ridgeway. It will specifically detail the on-scene behavioral analysis input provided to investigators of the abduction, homicide and dismemberment of Jessica. The presenter will discuss how these techniques assisted in narrowing the focus of the investigation, generated potential leads, formulated media strategies, interview strategies and assisted in the prosecution of the offender. The presentation will conclude with a dialogue, based on the post-offense behavioral interview of offender Austin Sigg, highlighting his pre-offense behavior, victim selection, and possible motives.
PRESENTED BY:
MARK L. MACKIZER, Special Agent - FBI Ret.
Mark retired after 27 years as a Special Agent with the Federal Bureau of Investigation where he spent most of his career conducting violent crime investigations. Mark held positions such as Crisis Management coordinator, Violent Gang Safe Streets Task Force coordinator, Evidence Response team member, and team leader for the FBI’s Southeast Region Child Abduction Rapid Deployment Team. The last 7 years of his career he was a Supervisory Special Agent assigned to the Behavioral Analysis Unit (BAU) where he was responsible for providing behaviorally based operational support to law enforcement involved in the investigation of violent crimes and threats.
Mark co-authored Crimes Against Children: Behavioral and Investigative Perspectives and the third edition of the FBI’s Child Abduction Response Plan.
Since retiring, Mark continues to provide operational behavioral analysis-based consulting services to government and private sector entities.
MARK L. MACKIZER, Special Agent - FBI Ret.
This presentation will cover
PRESENTED BY:
Detective Alison Carpentier, Westchester County Department of Public Safety
Alison Carpentier is a retired Detective with the Westchester County Police Department, where she served for nearly three decades in a variety of investigative and operational roles. She began her career in 1988 as a patrol officer, spending nine years policing the highways of Westchester County before being promoted to Detective in 1997. As a detective, Alison worked undercover investigating narcotics operations and sex trafficking cases. She later served in the Major Crimes Unit, handling high-profile investigations, including homicide, organized crime, and child abuse throughout Westchester County. She was trained by the FBI as both an instructor and hostage negotiator, and spent more than 15 years on the Hostage Negotiation Team, responding to critical incidents and helping resolve dangerous situations safely. Over the course of her career, she received more than 25 commendations, including two life-saving awards. After retiring from law enforcement, Alison continued her investigative work with the New York State Attorney General's Office, where she investigated corruption in the City of Yonkers. She later concluded her investigative career at Citibank as the Assistant Vice President in the fraud department.
Alison Carpentier, Detective (Ret.), Westchester County Police Department
Detective Sergeant Terry Wilson, Rye Brook, NY Police Department
DETAILS COMING SOON...
PRESENTED BY:
JASON NEWLIN, CHIEF INVESTIGATOR. Office of the State Attorney 2nd Judicial Circuit of Florida
Historically, the City of Flint has been home to traditional gangs such as the Bloods, Crips, and Spanish Cobras, each with defined territories, membership, and rules. That landscape changed dramatically in 2021 following the killing of 16 year old Nicholas Collins, which was soon followed by the retaliatory killing of his rival, Tayveon Crowder. These homicides gave rise to two new gangs, “Nick Mafia” and “Tay Mafia.” Both have rapidly grown into dominant forces in Flint, significantly reducing the influence of the older gangs. Unlike their predecessors, Nick Mafia and Tay Mafia do not operate within fixed geographical boundaries. Their influence extends beyond Flint into surrounding communities and local high schools, and member allegiance is fluid, with individuals often switching sides.
Since 2021, approximately 32 homicides and countless felonious assaults have been attributed to the conflict between Nick Mafia and Tay Mafia. Investigations have also led to the confiscation of hundreds of firearms and thousands of dollars. Their criminal activities have forced us to adapt investigative techniques, patrol strategies, methods of gang member identification, and to increase engagement with local high schools and the prosecutor’s office.
During the presentation:
- D/Sgt. Sarah Combs, Flint’s local gang expert, will provide an overview of Nick Mafia and Tay Mafia. She will explain how their nontraditional structure has expanded into suburban communities, detail their “cash card” scheme that has generated millions of dollars nationwide, and discuss how a recent court ruling in Battle Creek, MI has impacted gang membership identification and the application of gang enhancement charges. Sgt. Combs has already presented this material numerous times to local judges, high school staff, neighboring police departments, and Flint patrol officers.
- D/Sgt. Donny Scott will present on the Tayveon Crowder (AKA “Tay”) homicide investigation which occurred on August 10, 2021. The killing of Tayveon Crowder is the origin story of Tay Mafia. Sgt. Scott took over the case after it remained unsolved for two years. He will outline his investigative methods, including extensive social media analysis, numerous interviews, phone search warrants, and dissection of rap videos. His investigation revealed that the suspect, Kiandre Cannon, was the nephew of a local assistant prosecuting attorney, Stephanie Cannon, who had been handling other Nick and Tay Mafia related cases. After Stephanie Cannon’s house was shot up where approximately 50 rounds were shot into her home, Sgt. Scott uncovered evidence that she had been aiding in concealing her nephew’s involvement in Crowder’s killing. Sgt. Scott also uncovered that Kiandre was paid for the homicide by a head member of Nick Mafia from funds gained through the cash card scam. Kiandre was charged with the homicide and ultimately took a plea deal. Sgt. Scott has presented this case once before at a local conference.
- D/Sgt. Lashabriane Kelly will present on the double homicide investigation involving 13 year old Dontavis Moore and 15 year old Dominque Ward. This case highlights the escalation of the ongoing gang conflict, the growing audacity of its members, and the victimization of innocent family members. Dontavis and Dominque were killed on June 26, 2024, when someone walked up to their basement window and fired nine rounds into the house. Also in the home was Dontavis’ older brother, Demidrick Moore, a known Tay Mafia member, as well as his mother and her boyfriend who were both unharmed. Demidrick was also unharmed and fled the scene prior to police arrival. Sgt. Kelly’s investigation revealed that the intended target was Demidrick, who was on social media “trolling” rival Nick Mafia gang members after a homicide that had occurred just eight hours prior in the neighboring jurisdiction of Mt. Morris Township. Through numerous interviews, listening to hours of jail calls, dissection of rap songs, and cell phone search warrants, Sgt. Kelly identified the suspect, Ryan Davis, and learned that he received detailed information through text messages from Demidrick’s ex-girlfriend. The text messages told Davis where Demidrick lived and exactly in the house where he would be hanging out. On July 11th, Ryan Davis was arrested at the funeral of the Mt. Morris Township homicide victim while in possession of a firearm. Ballistic testing confirmed it was the same weapon used in the killings of Dontavis and Dominque. Davis was charged with double homicide and is expected to enter a plea.
- Lieutenant Mark Boudreau – Before Sgt. Combs became our gang expert, I studied the active gangs at the time and gave a few presentations on them prior to the existence of Nick and Tay Mafia. I plan to provide a very brief historical overview of those groups, which will also serve as an introduction to the three sergeants and transition into Sgt. Combs’ presentation.
PRESENTED BY:
Detective Sergeant Donny Scott
Detective Sergeant Sarah Combs
Detective Sergeant Lashabriane Kelly
Lieutenant Mark Boudreau
FLINT POLICE DEPARTMENT