Major Crimes was developed as a continuation spin-off of The Closer, set in the same LAPD division but now headed by Mary McDonnell's character Sharon Raydor. TNT had announced in December 2010 that the seventh season of The Closer would be its last, a decision made by star Kyra Sedgwick.

The final season of The Closer was expanded by six extra episodes specifically to build toward the possible spin-off, and in May 2011 TNT officially picked up Major Crimes for a 10-episode first season.

Most of the main cast continued their roles directly from The Closer, including Mary McDonnell, G. W. Bailey, Tony Denison, Michael Paul Chan, Raymond Cruz, Phillip P. Keene, Robert Gossett, Jonathan Del Arco, and Jon Tenney.

Detective Amy Sykes, played by Kearran Giovanni, is the only main character who did not previously appear on The Closer.

Graham Patrick Martin's character Rusty Beck had only appeared in two episodes of The Closer, both in its finale, before becoming a central character in Major Crimes.

The series premiere, boosted by airing right after The Closer's series finale, drew 9.5 million viewers, the largest audience ever for a series premiere on basic cable at the time, and the first season posted the highest ratings for any new show on cable.

Major Crimes received 'generally favorable' reviews, scoring 65/100 on Metacritic based on 17 critics, though some critics like Mike Hale of The New York Times felt it lacked the vividness of Kyra Sedgwick's performance from The Closer.

TNT renewed the series for a 13-episode sixth season in January 2017 during season five, but announced in October 2017 that this sixth season would be the show's last, ending after a total of 105 episodes.