The linebacker and defensive co-captain was charged with driving under the influence after being arrested in Denver early Friday morning, just hours before he was supposed to report to work at Dove Valley.
It's his second such arrest. He pleaded guilty in September 2005 to driving drunk and was ordered to perform 24 hours of community service. After that, he said he realized he needed to get a designated driver whenever he went out partying, and the team provides drivers to its players but Williams didn't use one Friday.
District attorney's spokeswoman Lynn Kimbrough said Williams was pulled over at 2:40 a.m. Friday for driving without headlights on. He was cited with DUI, a misdemeanor, as well as driving without headlights.
He was ordered to appear in court Dec. 13.
"We're certainly disappointed and don't condone that behavior from any of our players or anybody within our organization," coach Josh McDaniels said.
Williams, a seventh-year pro from the University of Miami, will likely be suspended for multiple games for violating the NFL's personal conduct policy. San Diego receiver Vincent Jackson is serving a three-game suspension for multiple DUI arrests, which was reduced from an original four-game penalty.
A conviction isn't required for NFL Commissioner Roger Goodell to suspend a player without pay. The league's policy states: "If the Commissioner finds that ... the player has had prior drug or alcohol-related misconduct, increased discipline up to and including suspension may be imposed."
It could take time for the league to review Williams' case, so there's a chance he could still play Sunday.
Williams showed up only briefly at the team's headquarters just before noon Friday before driving off while his teammates were at practice.
The Broncos (2-6) face the league's top rushing team Sunday when the Kansas City Chiefs (5-3) visit Invesco Field.
"We don't know that yet," McDaniels said when asked about Williams' availability for Sunday. "I don't know all the facts on that and this is going to involve more people than just us but we're certainly going to do what's in the best interest of our organization."
If he doesn't play, other options include inserting Wesley Woodyard or Joe Mays at his position at right inside linebacker or moving outside linebacker Mario Haggan back inside and playing Jarvis Moss on the outside.
None of those options are better than Williams, the fierce tackler whose leadership has been praised profusely by McDaniels and defensive coordinator Don Martindale in recent weeks.
Williams' trouble comes just as the Broncos were talking about getting healthy following their bye week and exuding an optimism about salvaging their season and getting back into the AFC West race.
The Broncos have relied on Williams more heavily this season with outside linebackers Elvis Dumervil (chest) and Robert Ayers (foot) sidelined, and he's responded with a team-leading 3½ sacks and a team-best 57 tackles, which put him on pace for a career-high 114.
That Williams is a captain made his arrest all the more disheartening to an organization that's been shrouded in negativity during a monthlong skid that included a 45-point loss at home to archrival Oakland.
"It's disappointing no matter who it is," McDaniels said. "The behavior and the fact we're two days away from a game is very disappointing to me and our entire organization."