He played one season in 2016 before being released by the Lions, and had brief stints with several other NFL teams.
According to court documents, Mr. Williams, 31, was seen on video footage of riots at the Capitol, where thousands of Trump supporters stormed the building after his 2020 election defeat, pulling up barricades and punching a police officer in the head and fighting with other officers.
Prosecutors say he remained on the Capitol grounds until the evening of January 6.
He was identified by a golf hat and a distinctive key ring he was wearing during the riots, which match other photos of Mr Williams online.
Internet volunteers known as “riot hunters”, who use online videos and pictures to hunt down rioters, identified the brand of the hat and gave Mr Williams the nickname “RiotingGolfer”.
More than 1,500 people were arrested in connection with the riots when a crowd of Donald Trump supporters stormed the US Congress building in an attempt to stop the certification of Joe Biden’s victory in the 2020 presidential election.
Donald Trump has promised to pardon some of those involved in the riots, although he did not specify what criteria he would use to do so.
Several people convicted or charged in the riots have asked to delay their trials or sentencing hearings because Trump’s pledge could affect their cases. Two judges adjourned those hearings Thursday, but other judges rejected similar motions.
The FBI is still seeking to identify dozens of other suspects who were present at the Capitol that day.
