Payback was the first ever episode of SVU.

Although later episodes reveal that Benson's mother was an alcoholic and verbally abusive to her, Serena Benson is portrayed in this episode as caring and loving. She asks Benson whether or not she would have been better off without her, to which Benson lovingly holds her mother's hand.

While Olivia and Serena Benson are enjoying lunch, the waiter pours wine into both their glasses. This is somewhat strange since later episodes state that Serena has a serious drinking problem.

John Munch: Not to mention the fact that I lost a wife after less than one night of connubial bliss to someone who was not only a detective but a member of my own squad.
Munch is refering to the final episode of Homicide: Life on the Street, where his character married Billie Lou Hatfield. Billie Lou left her husband for a former detective on the force, Stuart Gharty. Munch's presence in New York is explained by saying that he retired from the Baltimore police force, and is reaping the benefits associated with collecting a pension in Baltimore and a salary in New York.

Goof: While Benson and Stabler question Spicer at Rikers Island, Benson writes notes using a ballpoint pen. In close shots, it s evident that the pen is not clicked 'out', thereby making it impossible to write with it.

Elliot Stabler: Have you ever seen that Tom Hanks movie where he manages a baseball team?
In the film A League of Their Own, Tom Hanks manages a women's baseball team.

Kloster's Lawyer: So you see yourself as the 'Ken Starr' of the N.Y.P.D.?
Ken Starr was a special prosecutor appointed to preside over the Whitewater investigation in the mid-1990s. His role in the investigation into then-president Bill Clinton's involvement has been a topic of controversy for many years.

Elliot Stabler: Oh, I'd hurt you.
Stabler makes this comment in response to being hit on by Spicer at Rikers Island. In the HBO series Oz, Chris Meloni (Stabler) played the character of Chris Keller from 1998 to 2003, who had a nasty habit of killing his male lovers. Meloni is not the only regular from Oz to show up on Law & Order: Special Victims Unit -- Dean Winters, Lance Reddick, B.D. Wong and J.K. Simmons also had regular roles on Oz.