The cancellation was announced May 13, although according to reports, the show's executive producer, Dick Wolf, had been talking with NBC through the evening of May 12, apparently in an attempt to work out a deal for a 21st season for the series. If a deal had been reached, "Law & Order" would have broken "Gunsmoke"'s record as history's longest-running prime-time television drama.

NBC did announce that a fourth spin-off of the series, "Law & Order: Los Angeles" (or "LOLA") has been ordered, and that "Law & Order: Special Victims Unit" has been renewed for a twelfth season. The fate of the series' second currently running spin-off, "Law & Order: Criminal Intent," was not mentioned but will be made official when NBC announces its full 2010-2011 season May 17.

Four-hundred and fifty-six episodes of "Law & Order" have been produced since its premiere in September 1990. According to the Times, it is estimated that more than 8,000 people are employed by the series – nicknamed the "mothership" of the franchise – and its two running spin-offs. Those employees include many New York theatre actors. Stage notables who have been regulars on the show at one time or another have included Sam Waterston, S. Epatha Merkerson, the late Jerry Orbach, Jesse L. Martin, Steven Hill, Michael Moriarty and Annie Parisse, among others. It has become almost a rite of passage for thespians in the area to make at least one guest appearance on the series or one of its spin-offs between (and often during) theatre gigs.

Gina Gionfriddo, a Pulitzer Prize finalist for Becky Shaw, has worked as a writer for the show.

One of the show's executive producers, Fred Berner, was outside a Broadway theatre when he heard the news. He told the Times, "I guarantee you, every name in the Playbill will have appeared on 'Law & Order,' one of the three shows," calling the show's cancellation "a kick in the gut to New York."