Aldon Smith was forced to sit out the entire 2016 season. (Thearon W. Henderson/Getty Images)

Raiders defensive end Aldon Smith is under investigation by San Francisco police for an incident of domestic violence, according to multiple reports. The 27-year-old has been suspended by the NFL since November 2015 for violations of its substance-abuse policy, and the latest development could complicate his hopes of reinstatement.

As first reported by TMZ Sports, police arrived at a residence owned by Smith early Saturday morning, and they interviewed Smith and his alleged victim. The former 49ers player, taken by the team with the seventh overall pick in 2011, was not arrested but is under what the website was told is an “active investigation.”

A San Francisco police spokeswoman told USA Today that Smith is cooperating with the investigation, as is the woman who filed the complaint. No charges have been filed to this point.

Smith had been suspended for a calendar year, and he could have been reinstated late last season, but the NFL reportedly deferred making a decision until March. He was released by the 49ers in August 2015 after his fifth arrest with the team, his third for DUI. The Raiders signed him before that season and he played nine games for them, posting 3.5 sacks, before receiving his ban.

Despite his sidelined status, Oakland re-signed Smith to a two-year deal in April, hoping to eventually pair him again with another talented pass-rusher, Khalil Mack, the 2016 Associated Press defensive player of the year. In Smith’s first two NFL seasons, the only ones in which he played all 16 games, the Missouri product accumulated 33.5 sacks and was selected for the 2012 Pro Bowl.

Smith served a nine-game suspension in 2014, also for substance-abuse violations, and in July, he reportedly checked into a rehab facility just days after a video emerged that appeared to show him smoking marijuana.

If charged with domestic violence, that could prove to be a major issue for both the NFL and Raiders owner Mark Davis, who has spoken out on the issue. “It’s just something we can’t tolerate,” Davis told the San Francisco Chronicle in 2015. “I don’t know how to fix it in society, but I know we can’t have it on our team.”