A state appellate court Wednesday upheld the validity of the LAPD's Special Order 40, the controversial policy that bans officers from asking the immigration status of crime victims and witnesses.

In affirming a lower-court ruling, the three-judge panel said the 30-year-old order strikes the appropriate balance between immigrants' rights to equal protection and the Los Angeles Police Department's need to protect communities.

In 2006, a conservative organization and a Los Angeles resident filed suit to challenge Special Order 40, saying it violates federal immigration law and asking the court to prevent the use of taxpayer money to enforce the order.

The American Civil Liberties Union, which contested the suit on behalf of domestic violence victims, lauded the ruling by the California Court of Appeals.

"Immigrants in Los Angeles no longer have to worry that they will be forced to choose between personal safety and their future," ACLU attorney Belinda Escobar Helzer said in a statement.

"The court understands, as does the LAPD, that stripping away Special Order 40 would have not only violated the law but been a grave mistake in a city with such deep immigrant roots."

Former Chief Daryl F. Gates adopted Special Order 40 as a way to encourage immigrants to cooperate with the Los Angeles Police Department.

It has been supported by every chief since then, including Chief Bill Bratton.

Similar orders have been adopted by police departments in other U.S. cities where there are large immigrant populations. Critics, however, maintain that the order allows illegal immigration to flourish.

Mayor Antonio Villaraigosa also supported the ruling.

"The mayor agrees with Chief Bratton and virtually every other police chief in the state that forcing local cops to do the work of federal agents would lead to fewer arrests, fewer prosecutions and fewer convictions," spokesman Matt Szabo said.