The U.S. Supreme Court declined to hear a petition by the parents of Derek Boogaard in one of the earliest concussion-related cases brought against the National Hockey League.

The Dec. 3 ruling not to review the case brings to an end the five-year-old litigation by Len and Joanne Boogaard alleging the NHL should be liable for their son’s death as a result of the many concussions he suffered over his career.

Boogaard, who played for the Minnesota Wild and the New York Rangers, died in 2011 at age 28 after an overdose of opioids prescribed by team doctors for injuries, according to the family’s complaint.

An autopsy confirmed he suffered from chronic traumatic encephalopathy, or CTE, a degenerative brain condition associated with ice hockey and other head-banging sports.

The Boogaards, who sued in 2013, argued a trial judge improperly dismissed their suit under a Minnesota procedural rule requiring that wrongful death and survival actions be brought by a court-appointed trustee.

But the U.S. Court of Appeals for the Seventh Circuit found in May that the case couldn’t proceed for another reason.

The family “forfeited” its claims by failing to respond to the NHL’s argument that the complaint failed to adequately allege claims against the league.

When the U.S. District Court for the Northern District of Illinois dismissed the suit in 2017 it warned its ruling “should not be read to commend how the NHL handled Boogaard’s particular circumstances—or the circumstances of other NHL players who over the years have suffered injuries from on-ice play.”

Corboy & Demetrio represented the Boogaards. Proskauer Rose LLP represented the NHL.

The case is Boogaard v. Nat’l Hockey League, U.S., No. 18-419, review denied 12/3/18.