CHEYENNE, Wyo. (AP) - In a first for Wyoming, a court has ordered a post-conviction test of DNA in a 23-year-old sexual assault case. The Wyoming Tribune-Eagle reported Monday (http://tinyurl.com/ar47zcd ) that District Judge Thomas Campbell issued the order in the case of Andrew Johnson. Johnson was convicted of sexual assault and aggravated burglary in Laramie County in 1989 and was sentenced to life in prison. Johnson maintains his innocence. Seminal fluid collected in the case has not been tested for DNA. Johnson could be exonerated if the sample excludes him. According to the victim, Johnson broke into her apartment and sexually assaulted her.