Judge Maria Vargas from the episode "The Strange Secret of Bruce Wayne" appears in this episode as the arraignment judge.
Leslie: Aren't you going home? It's almost 3 am.
Batman: Promises to keep, Leslie. I have promises to keep.
Batman: When you look too long into the abyss, the abyss looks back through you. Maybe it's time for Batman to return to the night that spawned him before anyone else gets hurt!
Batman: I chose this life. I use the night, I became the night. Sooner or later I'll go down. It might be the Joker, or Two-Face, or just some punk who gets lucky. My decision. No regrets. But I can't let anyone else pay for my mistakes.
Leslie Thompkins: Santayana says that those who forget the past are condemned to repeat it.
Batman: He also said a fanatic is someone who redoubles his efforts while loosing sight of his goal.
Also available on the two-disc special edition of Batman: Gotham Knight as well as three other episodes.
This episode is episode 20 on the Batman: The Animated Series Volume 2 DVD.
Note the reference to the corner of O'Neil and Adams streets - a homage to Neal Adams and Denny O'Neil, the artist/writer respectively who are credited with reviving Batman as the somber "Darknight Detective" in 1970 with "The Secret of the Waiting Graves" (Detective #395).
Batman quotes philosopher, Friedrich Nietzsche, when he speaks, "If you stare into the abyss long enough the abyss stares back at you".
Batman's line, "Promises to keep, Leslie. I have promises to keep." is a vague reference to the poem "Stopping by Woods on a Snowy Evening" by Robert Frost, the last stanza of which speaks of promises to keep.
Both Leslie Thompkins and Batman quotes two slight variations of the philosopher's sayings: "Those who cannot remember the past are condemned to repeat it." and "Fanaticism consists in redoubling your effort when you have forgotten your aim."