A California Republican congressman on Friday would not apologize for a comment about immigrants he made in April in the context of Arizona's controversial new immigration law. 

The law requires that state law enforcement officials ask for identification from people they suspect are in the country illegally if they are stopped for other reasons. Critics say that could lead to racial profiling of Latinos.

Rep. Brian Bilbray -- a supporter of the law -- was asked on MSNBC in late April how officers could identify illegal immigrants without using ethnic characteristics.

"They will look at the kind of dress they wear," he said. "There is different type of attire, there is different type of -- right down to the shoes, right down to the clothes. But mostly by behavior."

Immigrants-rights protesters gathered outside Bilbray's district office on Friday and demanded an apology, according to San Diego 6.

The congressman told the network he would not apologize:

Bilbray spoke exclusively with San Diego 6 and when asked to give an apology he said, "Apology for what?"

Bilbray says he's done nothing inappropriate, that his comments come from years of experience interacting with the Border Patrol.  "Look, if you were raised along the border like I was -- if you had as much interaction with border patrol agents as I have -- you'd know that there's a whole lot of things that maybe the general public doesn't know about."