Sullivan, 50, pleaded guilty to involuntary manslaughter. His sentencing is slated for February 3.
Jackson County Prosecutor is reportedly asking Missouri lawmakers to pass "Blair's Law," which would make firing a gun in city limits a felony, with a few exceptions.
In July, prosecutors charged Sullivan with involuntary manslaughter and armed criminal action.
Sullivan and three other men were celebrating July 4 by firing a gun from the Whispering Lakes Apartment complex, where Sullivan reportedly worked as a security guard.
A stray bullet struck Blair Shanahan Lane in the neck, killing her while she was at a party at her uncle's home at 43rd and Pittman.