The lawyer, who declined to be identified because of grand jury secrecy, confirmed that federal prosecutors had agreed to get involved in the case in which a black lawmaker is accused of striking a white officer after he tried to stop her from entering a House office building without going through a security checkpoint.
U.S. Capitol Police Chief Terrance Gainer said McKinney turned the officer's failure to recognize her into a criminal matter when she failed to stop at his request, and then struck him.
"He reached out and grabbed her and she turned around and hit him," Gainer said on CNN. "Even the high and the haughty should be able to stop and say, 'I'm a congressman' and then everybody moves on."
"This is not about personality," added House Speaker Dennis Hastert, R-Ill. "It's not about racial profiling. It's about making this place safer."
For her part, McKinney wasn't backing down from the argument. She charged anew that racism is behind what she said is a pattern of difficulty in clearing Hill security checkpoints.
"This has become much ado about a hairdo," she told CBS News' The Early Show. McKinney, a Georgia Democrat, recently dropped her trademark cornrows in favor of a curly brown afro.
The police aren't the ones who are racist, one Republican said.