The FBI has launched an investigation into the death of former Indianapolis Colts owner Jim Irsay and the doctor who provided him with prescription pain pills and ketamine in the months leading up to his fatal overdose last May, according to documents obtained by the Washington Post and two people with knowledge of the situation.

A federal grand jury subpoena showed that the agency sought records and information in connection with Irsay's death, including his "substance (illegal and prescription) use," as well as his "relationship with Dr. Harry Haroutunian," a California-based specialist. The subpoena was issued from the U.S. District Court for the Central District of California in Los Angeles earlier this month and federal agents spent several days in Indianapolis during the investigation, conducting interviews with multiple people close to Irsay during his final years, two sources confirmed.

Irsay, 65, who had publicly acknowledged his battle with substance abuse, “spent the last two years of his life in the throes of a relapse," with an NFL executive claiming he was prescribed ketamine by a private doctor, who the executive claims, “signed Irsay’s death certificate, stating the cause was cardiac arrest.”

People close to Irsay were concerned over the treatment he received from Haroutunian prior to his death. Haroutunian reportedly prescribed more than 200 opioid pills prior to Irsay overdosing on two separate occasions in December 2023, with one incident taking place at his Indianapolis home and another at his Miami rental home.

Irsay's treatment eventually escalated to ketamine injections in the months leading up to his death, source with knowledge of the situation confirmed to the Washington Post as part of a previous report.

“I dedicated 18 months of my life to try to care for him … as a brother,” Haroutunian told the Washington Post in a phone interview before ignoring the newspaper's emails detailing its reporting. “We did everything we could to make him as comfortable as possible.”

Irsay's three daughters, Carlie Irsay-Gordon, Casey Foyt and Kalen Jackson, who have since taken over the Colts' ownership duties, issued a statement to the Indianapolis Star following the report.

“We continue to grieve the loss of our Dad, a man defined not only by his role as owner of the Colts, but also by his resilience, his personal struggles and his deep love for family, friends, and community,” the Irsay family said. “Throughout his life, our Dad was open about his battles with addiction and mental health. He never claimed to be perfect. Instead, he used his voice to reduce stigma and advocate for those facing similar challenges, with honesty, vulnerability, and compassion.”

Irsay initially took over the Colts' day-to-day operations after his father, Robert, suffered a stroke in 1995 and won a legal battle with his stepmother, Nancy, to retain ownership of the franchise following his father's death in 1997. Robert Irsay initially purchased the Los Angeles Rams and swapped the then-Baltimore Colts with the late Carroll Rosenbloom, at which point Jim worked as a ballboy during Pro Football Hall of Fame quarterback Johnny Unitas' playing career.

Jim Irsay became the NFL's youngest general manager at the age of 25 following the team's relocation from Baltimore to Indianapolis in 1984. The Colts have won one Super Bowl and two AFC titles, both of which came during Pro Football Hall of Famer Peyton Manning's 13 seasons at quarterback, since Irsay took over as team owner.