EL RENO — A judge Friday refused to allow murder defendant Joshua Steven Durcho a separate jury trial on whether he is mentally retarded.
Canadian County District Judge Gary E. Miller, though, agreed defense attorneys can have time to appeal his ruling.
The defense challenge to the Oklahoma Court of Criminal Appeals means Durcho's murder trial will be delayed again.
The murder trial was set to begin Feb. 6.
The 28-year-old faces five first-degree murder counts.
Prosecutors are seeking the death penalty.
Defense attorneys say they have evidence Durcho is mentally retarded and — because of that — is ineligible to be executed.
Prosecutors allege Durcho strangled his girlfriend, Summer Rust, 25, because she threatened to call police on him and he had vowed he would never go back to prison.
They allege he strangled her three daughters, Kirsten Rust, 7, Autumn Rust, 7, and Evynn Garas, 3, and her son, Teagin Rust, 4, to eliminate them as witnesses.
The victims' bodies were found Jan. 12, 2009, in their El Reno apartment.
Durcho has spent time in prison for marijuana possession.
At the time of the deaths, warrants were out for his arrest in a drunken-driving case and a methamphetamine case.