The pseudonymous LAPD cop "Jack Dunphy" gives an overview of Los Angeles' sanctuary city policy here:

...Since 1979, when the LAPD enacted Special Order 40, police officers in Los Angeles have been prohibited from taking any action "with the objective of discovering the alien status of a person," and from detaining or arresting anyone based solely on the suspicion that he has illegally entered the country. "Undocumented alien status in itself is not a matter for police action," the policy states. "It is, therefore, incumbent on all employees of [the LAPD] to make a personal commitment to equal enforcement of the law and service to the public, regardless of alien status."

...the LAPD is set to issue a directive intended to clarify what its officers should and should not do when dealing with criminal suspects believed to be in the country illegally. The measure was discussed last week at a meeting of the Los Angeles police commission, the civilian panel that oversees the city's police department...

...But the mere suggestion that the LAPD may reexamine the constraints that Special Order 40 places on its officers has triggered alarm in immigrants'-rights circles. "How do you make sure that the policy doesn't spill into other abuses?" said Linton Joaquin of the National Immigration Law Center. "Our concerns are that the [LAPD] not get into the business of immigration enforcement."

In other words, because there is risk of abuse, why do anything at all about the epidemic of crimes committed by illegal aliens? Such talk is falling on increasingly deaf ears these days, especially in those cities hardest hit by the crime wave Mac Donald described in her House subcommittee testimony...

In related news, there's some kind of a video apparently featuring Orange County Sheriff Mike Carona, former LAPD Chief Daryl Gates and LA Police Commission Presidents Edith Perez and Rick Caruso here. I didn't watch it and I don't know if it has exclusive interviews or compilations or what.