Attorneys representing Wyoming's lone death row inmate have filed a motion with the state supreme court to delay his Dec. 19 execution.

The motion, filed Friday on behalf of Dale Wayne Eaton, asked for the stay pending future legal proceedings, said Tina Kerin, appellate counsel for the state Public Defender's Office. Eaton was convicted four years ago of the 1988 kidnapping, rape and murder of Lisa Marie Kimmell.

Eaton's attorneys will be filing a petition with the U.S. Supreme Court and will also seek legal relief in the state court system, Kerin added.

A copy of the motion to stay the execution was unavailable Monday because the Wyoming Supreme Court was moving to another building.

Attorneys filed the motion less than two weeks after a Natrona County district judge set a formal date for Eaton, 63, to be put to death. The Wyoming Supreme Court rejected Eaton's appeal in August and directed the trial court to set a new date for his execution.

However, it remains likely that date will be pushed back as Eaton's attorneys seek relief in multiple legal venues. Natrona County District Attorney Michael Blonigen earlier this month estimated the legal process surrounding Eaton's death sentence is less than halfway through.

The case itself is already two decades old. Kimmell, 18, disappeared in 1988 while driving from Colorado to Cody. Fisherman found her body floating in the North Platte River eight days later.

She had been sexually assaulted, hit in the head and stabbed before being thrown from Government Bridge near Highway 220.

Prosecutors, with the help of DNA evidence, charged Eaton with her murder in 2003. A jury convicted him and sentenced him to death the following year.

Reach crime reporter Joshua Wolfson at (307) 266-0582 or at josh.wolfson@trib.com.