Danielito Valentin, 31, is charged with felony aggravated battery
The shooting happened in a dispute over an unpaid bar tab.
Valentin says the victim pulled a gun first.
He faces the impersonation charged after he reportedly admitted to carrying a Chicago police badge so he could pose as an off-duty cop.
Valentin was working the door at Gallagher's Bar in the 1700-block of West Greenleaf.