The Immigration and Naturalization Service is failing to crack down on California employers who hire illegal aliens because of political pressure and weak laws, a study concludes.

The study by the Rand Corp. and the Urban Institute concludes that the Immigration Reform and Control Act of 1986 has still compelled the INS to develop a framework to implement stricter laws if Congress passes them."In Los Angeles, the law is being implemented appropriately. It's not being implemented in a very strong, draconian fashion, but Congress probably didn't intend it to be," said Rand Corp. researcher Elizabeth Rolph, coauthor of the study with Abby Robyn.

Employers are required to make sure job applicants have legal documents, such as a valid drivers license or Social Security card.

But an INS official in Washington said that requirement is circumvented by the widespread availability of counterfeit documents, such as drivers licenses and Social Security cards.

Fraudulent Social Security cards can be purchased on either side of the border for about $25, said INS spokesman Duke Austin.