The Raiders signed him prior to the 2015 season, and he played nine games in silver and black.
The specifics of what exactly happened are unknown.
Smith has been in and out of trouble with the law throughout his entire career, and hasn't played in an National Football League game since 2015 due to multiple suspensions.
Aldon Smith is back in the news for all the wrong reasons.
Smith and an unnamed person who made the initial report are cooperating with police, San Francisco Police officer Grace Gatpanden said Monday. "I don't know how to fix it in society but I know we can't have it on our team". NFL Media reported last week that Smith is expected to be reinstated in March.
While it's possible nothing could come from this domestic incident - time will tell in that regard - it isn't a good look for someone hoping to get reinstated by the National Football League this spring.
Smith filed for reinstatement on October 3 before meeting with commissioner Roger Goodell. SN's Alex Marvez notes the Raiders have a zero-tolerance policy with regard to domestic violence. The final straw was a DUI, hit and run and vandalism charges in 2015.
Smith has missed 39 of a potential 64 games for the 49ers and Raiders over the past four seasons either under suspension or voluntary rehab.
The linebacker was allowed to apply for reinstatement after one year, which he did in November 2016.