By Jill Serjeant
LOS ANGELES (Reuters) - Almost all the Roman Catholic priests accused of child sexual abuse in California are likely to escape prosecution after a Supreme Court ruling on Thursday that struck down a law enabling the prosecution of old sex crimes.

"We expect all of these ancient cases to be dismissed...The witch-hunt is over," said attorney Don Steier who represents more than 20 Los Angeles-area priests accused of sex abuse, sometimes dating back decades.

"The practical result of today's decision is that virtually all of the cases involving accusations against local priests must be dismissed if they have already been filed, or dropped because they cannot be filed," Steier told reporters.

Ten former or current priests in the Los Angeles archdiocese alone have been charged with child molestation in the sex abuse scandal that rocked the Catholic Church last year and which is still moving through the California courts.

But the Supreme Court ruled 5-4 on Thursday that California cannot retroactively erase statutes of limitation for sex crimes against children.

The law was challenged by Marion Stogner, a 72-year-old man who was accused in 2001 of molesting his daughters when they were children almost 50 years previously.

But the implications of the Supreme Court ruling were felt most keenly among those involved in the Catholic Church sex scandal.

Lawyers representing several hundred alleged victims in civil claims against California priests expressed dismay at the Supreme Court decision, but said it should have no impact on pending civil cases.

JUSTICE UNOBTAINABLE

Los Angeles County District Attorney Steve Cooley said the decision meant that "many child victims of sexual abuse will not be able to obtain justice in a criminal court. Some sexual predators will escape criminal accountability.

Cooley said his office would now be unable "to pursue those offenses committed by clergy and others," and added that he would review more than 200 cases overall that could be affected by the ruling.

"I think pedophile priests are celebrating today because they will not be criminally prosecuted. But victims still have recourse through civil claims," said Kathy Freberg, a lawyer representing more than 100 alleged victims from San Francisco to San Diego in civil cases.

Attorney Raymond Boucher said the ruling was "anti-child protection" but said it might be advantageous for civil plaintiffs because priests would no longer be able to invoke their Fifth Amendment rights to avoid self-incrimination in potential criminal cases.

"At least we will get some more information when we take depositions," Boucher said.

The Los Angeles Archdiocese, which has been criticized by Cooley for obstructing the prosecution of accused priests, said the ruling would have no effect on its policy of permanently removing from the ministry any priest found guilty of sexual abuse.

"The Court's ruling does not make way for those men to reenter ministry or function in any way as priests," the Archdiocese said in a statement.