Jason Autry testified Thursday that he helped Zachary Adams unload Holly Bobo's body from a truck and served as a lookout while Adams shot her near a river on April 13, 2011. She was reported missing from her home that day.
Autry also told a prosecutor he used drugs before they drove to the river.
On cross-examination by defense attorney Jennifer Thompson, Autry said he injected what he called a "cocktail" of methamphetamine and morphine minutes before heading to the river. He also acknowledged failing to remember calls and texts he placed that morning.
Autry acknowledged that "once that euphoria kicked in, you could say my track of time was altered."
Later, Thompson asked if being high affects his memory.
Autry said: "That, and time, yes. We're discussing events that happened six years ago."