Detroit Lions RB C.J. Anderson was investigated by cops this year after he allegedly got violent with a ref at a youth football tournament ... but no charges were filed and the NFL stud is adamant he NEVER put his hands on the guy.
C.J. was coaching a 14-and-under team at a 7-on-7 event in Cypress, Texas back on March 2 when cops say he got into a spat with a referee over an on-field call.
A Harris County Sheriff's Office spokesperson tells TMZ Sports, Anderson allegedly got face-to-face with the 38-year-old official .