SAN BERNARDINO, Calif. (AP) — A judge on Friday denied news media requests to unseal documents in the case of a slain family of four whose bodies were found buried in the desert. He also ruled that the defendant may represent himself.

San Bernardino County Superior Court Judge Michael A. Smith said releasing the information could compromise the investigation and jeopardize the due process rights of Charles "Chase" Merritt, who is accused of murder.

Merritt's request to represent himself in the case was granted, but the judge said he needed written approval from a doctor saying that a medical condition would not be a problem. Merritt said his jail doctor did not believe it would be a problem.

Attorney Robert Ponce, who had been representing Merritt, said outside court that his former client has congestive heart failure.

The judge scheduled a preliminary hearing for April 7.

More than a dozen news organizations including The Associated Press had argued that San Bernardino County authorities can't keep case documents sealed because it is now a prosecution and not an investigation.

The motion sought the unsealing of search warrants, affidavits, statements of probable cause and returns related to the investigation. Release of the documents was opposed by the prosecution and defense.

Joseph McStay, 40; his wife, Summer, 43; and their children Gianni, 4, and Joseph Jr., 3, disappeared from their home in the San Diego County city of Fallbrook in February 2010. The case went unsolved until an off-road vehicle driver discovered their bodies in shallow graves in November 2013 in San Bernardino County.

A year later, San Bernardino County sheriff's officials arrested Merritt in their deaths.

Merritt pleaded not guilty to murder last year. Authorities have not revealed what led them to him nearly five years after the family disappeared.

Search warrants unsealed last week in San Diego County showed that police there found a tall lamp lying on a bedroom floor and open suitcases containing folded clothes in the walk-in closet of the McStays' home.

Two bowls of slightly spilled popcorn were on a living room couch and a carton of raw eggs and bowl of microwave popcorn were left on a kitchen counter.

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