Officials have determined Warrant singer Jani Lane died from alcohol poisoning ... law enforcement sources tell TMZ.
We're told the L.A. Coroner's Office has finished its investigation -- and concluded Lane had suffered from "acute ethanol poisoning" when he died in an L.A. motel room on August 11.
As TMZ previously reported, investigators found a half-empty bottle of vodka and prescription medication in the motel room where Lane died.
The singer had battled substance abuse issues for years.
Waiting for your permission to load the comments.