LEAVENWORTH, Kan. (AP) — The parents of a Leavenworth County teenager who has been missing since 1988 are going to court in an effort get criminal investigative records on their son’s case.

Harold and Alberta Leach of Linwood are suing Leavenworth County after county officials rejected a Kansas Open Records Act request for the criminal documents.

The couple’s 17-year-old son, Randy Leach, disappeared in April 1988 after a high school graduation celebration in rural Leavenworth County. Investigators found no trace of him and no one was been charged in the case.

The couple’s attorney, Maxwell Kautsch, says the law enforcement records would show whether Leavenworth County properly investigated the disappearance.

The trial is scheduled to begin Nov. 21.

The Topeka Capital-Journal reports the county’s attorney, David Van Parys, declined to comment.