In a letter to the district attorney's office, the mother of 16-year-old Joseph Loudon wrote, the investigation is "strangely out of focus and shockingly passive."
Marianne Payne claims police have dismissed evidence and refuse to hear possible tips.
Loudon died in May. Alcohol and a drug used to treat erectile dysfunction were found in his system.**
Police have not responded to the letter.
**Please Note: Since this report was first published, ABC7 has learned officials were incorrect in reporting Loudon died with papaverine in his system. It was learned on September 14, 2009 that an organ donation staff member injected the drug into Loudon's body after he died. More on that story here: Orinda teen didn't die with drugs in system