The pleas stem from incidents in March and June of this year, during which Clark was arrested both times on suspicion of having a concealed firearm in a vehicle. The district attorney's office told ESPN on Tuesday that Clark is due back in court on Jan. 17 for a preliminary hearing.
If convicted, Clark could face up to three years in prison. The district attorney's office, however, indicated to The Kansas City Star on Tuesday that it is still unclear what sentence the department will ultimately seek.
Clark was arrested in March, along with another man, when officers said they found two loaded firearms in their vehicle after a traffic stop, the Star reported at the time, citing California Highway Patrol records.
Clark was also arrested in June in Los Angeles in a separate incident in which police officers saw a submachine gun in his car. Clark's attorney, Alex Spiro, said at the time of his arrest on suspicion of having a concealed firearm in a vehicle, that the gun belonged to Clark's bodyguard.
In July, the Los Angeles County district attorney's office charged Clark with one felony weapons violation stemming from his arrest in March.
The NFL previously said it was reviewing the incidents under its personal conduct policy.
Clark wouldn't go into detail about his legal situation in a recent interview, the only one he's done since the start of training camp in July.
"My legal team is taking care of everything,'' Clark said. "I've been advised not to speak on it until further notice. My legal team is taking care of everything and I have full confidence in everything they're doing.''
Clark, who is a native of Los Angeles, has played in just one of the Chiefs' four games this season, missing the other three because of a hamstring injury. He was part of the Chiefs' Super Bowl-winning team in the 2019 season and overall has 50 sacks in 92 career games.