HEDWIG VILLAGE, Texas -- The family of a man who died after a police pursuit dispute the official autopsy.

They’re calling for federal intervention to help find out what really happened.

“We want to know what the hell happened to this young man!” said community activist Quanell X during a news conference.

The family of 21 year-old Darrall Thomas recruited Quanell X to try and find answers nine months after Thomas’ death.

“I’ve been to hell and back trying to figure out what happened to my child,” said Thomas’ mother, Lakita Carr.

They dispute what the Harris County medical examiner’s office determined. It states Thomas died from a drug overdose following a rescue from Hunter’s Creek.

That’s where Hedwig Village Police say Thomas ran after he and two others tried to steal an ATM from a nearby bank.

“He was on drugs, he was committing a criminal act, he ran from the police, and he died,” said Hedwig Village Police Chief David Gott.

The chief watched as Quanell X made more serious claims based on an outside forensic expert’s analysis.

“And this report says directly, the cause of death is homicide,” Quanell X said.

Actually, the report he provided states the cause and manner of death of Darrall Thomas is “undetermined.” It says drugs were in his system, but not enough to kill him.

“That is a long way from claiming it was a homicide,” Chief Gott said.

The chief says Houston Police conducted the initial investigation, and he’d welcome another.

Thomas’ mother says she’s willing to wait however long justice, for her, may take.

“It’s been tough, but we’re making it through with the grace of God,” Carr said.

Quanell X says the outside autopsy review suggests Thomas may have drowned in the creek, although that isn’t specifically stated.