Sources tell Bonsignore that Westbrooks was pulled over by Bakersfield police for speeding and found a gun in a vehicle that was not registered to him.
Westbrooks was arrested and taken into custody and later released on bail.
Westbrooks was facing five felony charges including receiving known stolen property, carrying a loaded firearm, carrying a loaded stolen weapon, grand theft of firearm and possessing a high capacity large magazine.
All five are felony charges.
Last year, Westbrooks was arrested on suspicion of domestic violence in Sacramento, but the district attorney declined to file charges in the matter.
The Rams just signed Westbrook to a one-year extension that includes a pay cut from his $1.797 million restricted tender down to $1.25 million. In 2018, Westbrook stands to make a base salary of $1.75 million.
Westbrooks, 26, wound up signing on with the Rams as an undrafted free agent out of West Texas A&M back in 2014. He played out his rookie contract with the Rams before receiving an original-round tender a few months ago.
This season, Westbrooks has recorded three tackles, a sack and a pass defense over the course of three games for the Rams. Pro Football Focus has him rated as the No. 43 interior defender out of 123 qualifying players.