Saenz, a former lawyer for the Mexican American Legal Defense and Education Fund, has pushed for anti-discrimination protection against Border Patrol sweeps.
For his part, Perez appears to have achieved little, if any, public prominence on hot-button immigration issues, despite his involvement with CASA de Maryland, an immigrant advocacy group, on whose board he served from 1995 to 2002, including as president. He also was on the board of the National Immigration Forum for just over a year in 2004 and 2005.
The Takoma Park resident spent seven years at the Justice Department as an attorney in the civil rights division and was a Clinton administration appointee as head of the Office of Civil Rights at the Department of Health and Human Services.
Cruz Reynoso, who served with Perez as an Obama transition team leader on civil rights, said he had no inside information about Obama's decision to appoint Perez.
But in an interview, Reynoso, the first Latino to serve on the California Supreme Court, said he was "a little bit disappointed, frankly, that if what I hear is true, it may mean that the president is not willing to enter into the fight that I think we have to enter into to do any good on immigration."
The civil rights division deals with a wide range of anti-discrimination enforcement. But historically, immigration is "not a major issue" for its lawyers, said Joseph Rich, a former chief of the voting rights section.
Richard Simon of the Tribune Washington bureau contributed to this article.
