Next time the GOP whines about immigration, remind them about the Civil Rights Division in the Bush era Justice Department.
You want to talk about "Prosecutorial Discretion" and Presidents deciding how and when to enforce the law?
When George W. Bush came into office, his administration basically decided to stop prosecuting civil rights cases.
From the Washington Post, in June of 2010:
When Thomas E. Perez took over the Justice Department's Civil Rights Division in October, he found an office that was a shadow of its historic self.Nearly 70 percent of the lawyers had left between 2003 and 2007, a mass exodus that came during allegations the Bush administration was politicizing hiring. Internal watchdogs concluded that the division's former head had refused to hire lawyers he labeled "commies" and had transferred one for allegedly writing in "ebonics," allegations the official denied. Civil rights groups said the unit had lost its traditional civil rights focus.