The Real Reason Jeffrey Donovan's Detective Frank Cosgrove Left Law & Order

"Law & Order" fans had to deal with yet another shift in the casting department when the series bowed for Season 23. Frank Cosgrove (Jeffrey Donovan) is officially out as a regular presence on the show and has been replaced by Vincent Riley (Reid Scott), who is Jalen Shaw's (Mehcad Brooks) new partner. TV Line reported in November 2023 that Donovan's exit came about due to creative differences, which were ultimately unresolvable. At the moment, Donovan doesn't have any further projects on his slate, which leaves the possibility of a guest appearance on the table in the future.

In "Freedom of Expression," the show's Season 23 debut, Riley and Shaw converse about Cosgrove's departure, which they explain came about due to Cosgrove's honesty. "Great cop, just got jammed up. Being too honest about things people aren't too honest about these days," Shaw explains. That implies that Frank has placed his value system over whatever mandate the force tried to keep in place. Cosgrove seems to have parted from New York's finest in a manner that leaves the door open and upholds his reputation as a figure of integrity and truth. But, naturally, he isn't the first actor to leave "Law & Order" since the show made its auspicious debut on NBC decades ago.

Jeffrey Donovan was brought into the "Law & Order" fold in 2021 when the series rebooted, but even during his two seasons on the program, cast shuffling caused the makeup of the show's core chemistry to change. Frank Cosgrove's first partner was series vet Kevin Bernard (Anthony Anderson). Between Season 21 and Season 22, Anderson left the program, declining to extend what was a single-season agreement.

Bernard was written out of the show and replaced by Shaw, who transferred over from another precinct. Cosgrove and Shaw only had a single season to hone their chemistry before Cosgrove, too, left the precinct. Fans shouldn't be too worried that this is an indicator that the "Law & Order" reboot is in trouble; it's long been a series that has seen main cast members come and go. Dozens of detectives have left the roster over the years, but, hopefully, the partnership between Shaw and Riley will be much longer-lasting.