The street gang that Bruce and Alfred visit for information is called The Mutants, a nod to the gang in Frank Miller's 1986 comic 'The Dark Knight Returns.'
When Alfred and Bruce went to the "fight club", one of the fighters was shouting Solomon, and the other called back Grundy. This is in reference to the DC villain Solomon Grundy.
Lori Petty is no stranger to the DC universe. She previously provided the voice for a character in the animated series of Superman known as Livewire, a shock jock who was openly cynical about the Man of Steel, and was not a fan of the police.
In the comic universe Matches Malone is an alias used by Batman when going undercover in the underworld.
In the comics, Bruce's parents are actually killed by a guy named Joe Chill.