Now, investigators say it could be weeks before authorities determine the exact cause of his death.
The Merced County Sheriff's Office says the cause of death will not be determined until after the toxicology report is complete.
But investigators are releasing new details about Abston's life.
This picture taken by an Action News viewer captures the end of a strange stand-off that now has authorities searching for answers.
53 year old Richard Abston died at the hospital less than an hour after he was tasered by a Merced Police Officer Thursday morning. Before his arrest, officers say Abston drove down Highway 99 in the wrong direction, ran from officers, and resisted arrest.
An autopsy was performed at the Merced County Coroner's Office Friday morning, but the pathologist is waiting to release a cause of death until the toxicology report is complete.
Deputy Tom Mackenzie, Merced Co. Sheriff's Office: "What they do is they take body fluid, blood and tissue samples and they send them off to see what kind chemicals were in his system at the time."
Deputy Tom Mackenzie says the report will show whether Abston had any alcohol, medication, or illegal drugs in his system, as well as any unusual levels of the body's natural chemicals. But as authorities wait for answers about Abston's death, they are also searching for details about his life.
Deputy Tom Mackenzie: "Through investigation our detectives did learn that he had an address in Modesto last year. But it's a P.O. Box and it's no longer valid, so we believe him to be a transient at the time of the incident."
Action News has also learned Abston had a criminal record that included a petty theft charge in Fresno County and other criminal charges in the Bay Area.
The Merced Police Department has said it does not believe Abston died as a direct result of being tasered.
We should know more in about three to four weeks when the toxicology report is expected to be complete.
