Brittany Murphy‘s mother and father are determined to prove that the actress didn’t die of natural causes.

Angelo Bertolotti is now suing the Los Angeles County Coroner’s Office because he disagrees with the official cause of death.

According to RadarOnline, Brittany’s dad is trying to gain access to his late daughter’s hair samples, so he can conduct his own testing.

Bertolotti claims “testing/toxicology was incomplete and the death of Brittany Anne Murphy Monjak was never fully investigated.”

Bertolotti, who is also suing the Los Angeles Police Department.

“I’m not going to rest until my daughter’s untimely demise is properly investigated, which hasn’t happened so far. Her case deserves more than a superficial glance.” Bertolotti said in a press release.

Can’t say I blame him.