Robert Harris is charged with causing injury while operating a vehicle under the influence of a controlled substance.
WISN-TV quotes prosecutors as saying Harris had cocaine in his system when he ran a red light and hit Steve "The Homer" True's car in November.
According to the criminal complaint, Harris also admitted he was drinking. True suffered a serious head injury.
True was released from the hospital a couple days later and returned to his job the next week as a sports talk show host on Milwaukee's ESPN station WAUK. He also does play-by-play for Marquette University basketball, which he's done for more than 20 years.
True previously worked for WISN-TV.