MAN FACES 27 YEARS EX-CON LINKED TO PROSTITUTE'S DEATH.

Byline: KAREN MAESHIRO Staff Writer

LANCASTER -- A registered sex offender faces 27 years in prison after pleading no contest to voluntary manslaughter in the 1999 death of a Lancaster prostitute.

Ronald Lynn Rook, 39, was charged with kidnapping, sexually assaulting or robbing four women who worked as prostitutes along Sierra Highway from 1999 to 2003, and of murdering Twila Ann Martin, 40, who was found beaten to death on a desert dirt road.

Rook entered his plea last Wednesday after prosecutors agreed to dismiss murder and other charges, citing insufficient evidence.

Investigators initially arrested an ex-convict friend of Martin whose home she had visited the morning before she was killed. But he was cleared based on DNA evidence.

``The only evidence we had to connect Rook to the victim was his DNA under her fingernails. The criminalist could not tell us how long that DNA had been there, and there was significant evidence of another person possibly committing this crime. The evidence against that person looked pretty good until DNA came back,'' said Deputy District Attorney Kerry White, Antelope Valley's head deputy.

White said Rook had a history of using prostitutes.

Rook, who also admitted a prior ``three strikes, you're out'' conviction, must serve 85 percent of the sentence. He remained in custody without bail and is scheduled to be sentenced Tuesday.

Martin's body, clad in a T-shirt and bra, was found Feb. 28, 1999, in the middle of a dirt road near Avenue L-8 and 15th Street East.

Martin was a mother of two who family members said tried but was unable to kick a drug addiction.

Martin had vowed to change her life. She married and moved to Ohio, but divorced soon after. Both of her children were taken away from her when she started using drugs again, friends said.

After a two-day preliminary hearing in March 2005, a judge ruled there was enough evidence to try Rook on 12 of the 14 charges made against him.

Two rape charges were dismissed after one of the four women said she had sex willingly with Rook after he picked her up, but that Rook then pulled out a gun and robbed her of the money he paid her.

Rook, an ex-convict who got out of prison in 1997 after serving a sentence for assault with a firearm, was linked to Martin's slaying in 2004 by an ongoing check of a DNA database containing samples from convicted felons.

Rook was arrested in November 2004 while working on a Santa Clarita assembly line.

The other three women's cases were linked to Rook after homicide investigators reviewed Antelope Valley rape cases dating back to when Rook got out of prison.

Detectives also reviewed other local killings of women who worked as prostitutes -- of which at least five were between 1994 and 1999 -- but in every case where there was DNA evidence, it eliminated Rook as the killer, investigators said.

Detectives say they have no proof that a serial killer was responsible for the women's deaths. Drug-addicted prostitutes live dangerous lives, and are vulnerable to boyfriends, customers and drug suppliers, detectives said.

A Lancaster man convicted of kidnapping and raping prostitutes was investigated in the deaths of three women in 1996 and 1997, but DNA evidence cleared him in the killings.

Martin died while that man was in jail awaiting trial on rape and kidnapping charges, for which he was convicted and sentenced to 181 years to life in prison. Two of the other women died while Rook was in prison on the assault charge, records show.

karen.maeshiro(at)dailynews.com

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