Hilbert Thomas (January 11, 2011)

Prosecutors are seeking the death penalty against a Garden Grove man accused of executing a Costa Mesa man and his co-worker during a robbery last year in Stanton.

Because of the seriousness of the alleged crime, and the nature of the slayings, a panel of Orange County district attorney prosecutors are seeking the death penalty against Hilbert Pineil Thomas, 39.

Thomas is accused of shooting, execution-style, Costa Mesa resident Matthew Francis Scott, 42, and his coworker Elizabeth Ann Palmer, 50, of Fountain Valley, on Feb. 2, 2010 at Golden Sun Homes in Stanton.

Scott's father owns the business, which sells manufactured homes.

The morning of the killings, Thomas walked his niece to her nearby school and on the way, passed Golden Sun Homes and saw Palmer's parked white, 2004 Lexus GS300, prosecutors assert.

Authorities argue sometime soon after that, Thomas decided to steal the car, walked into the Golden Sun Homes front office and immediately shot both Palmer and Scott in the head.

It was not clear if Thomas stopped at home first to grab a gun after dropping off his niece, officials said.

He lived only about 500 feet from where the killings took place.

For months detectives had no leads on a motive for the killings or who shot the pair. Nothing was missing from the victims or the business except for Palmer's car. There was also no evidence of a struggle.

In October, detectives spotted the Lexus in an Anaheim motel parking lot without the right license plates. Thomas was arrested soon after.

Two weeks before his arrest, Orange County authorities served Thomas a protective order requiring him to turn over any of his firearms to police because he'd set his ex-wife's car on fire in Los Angeles County. At the time they did not know he was allegedly linked to the Stanton killings.

Thomas is charged with two special circumstances murders, including enhancements for killing during a burglary and robbery.

He is being held without bail and due back in court for a pre-trial hearing on Feb. 4 at the Central Justice Center in Santa Ana.