TV producer and writer Dick Wolf quietly created a TV phenomenon when he brought Law & Order to NBC in 1990. With a novel format in which detectives investigate a crime in the first half of an episode that’s prosecuted in the second half, Law & Order ran for 20 seasons and spawned six other police dramas, most notably the sensitive crimes-oriented Law & Order: Special Victims Unit, launched in 1999 and still going strong.

As both series track a crime through the "law" and "order" channels, Law & Order shows necessarily require large casts to portray their various detectives, police administrators, prosecutors, and defense attorneys. And as both shows have been on for decades (they’re two of the three longest-running primetime dramas in TV history), that means they’ve seen dozens of actors come and go with the franchise. So here’s a look at some of the major cast upheavals in Law & Order history and the real reasons why these actors left the franchise.

Chris Noth couldn’t get the money he was owed

Among all the many men and women who shot to fame by playing a good guy cop or crusading district attorney on a Law & Order series, Chris Noth was the first. First introduced in the pilot episode, Noth portrayed the show’s first junior detective, the tough and swaggery Mike Logan. Despite the success of the show and the popularity of Noth’s character, Detective Logan was written out in 1995, forcibly transferred to a Staten Island unit after he punched a politician on trial for murder.

In reality, Logan had to leave because Noth had to leave, as producers let him go after five seasons with the series. The reason? Money. Scheduled contract renegotiations were about to begin, producer Dick Wolf told the Associated Press, and Noth would’ve been entitled to a "huge" salary bump if he were to stay on for a sixth season. According to Wolf, that raise would’ve been "impossible to grant." But according to the other side, Noth was okay with moving on to bigger and better things. "He’s really sorry that they couldn’t get it together, but he’s had five great years, and his feeling is that it’s time to move on," said Dolores Robinson, head of Noth’s management team, and the actor did indeed go on to find success on TV shows like The Good Wife and Sex and the City.

Fred Thompson had his eye on the White House

As Law & Order‘s no-nonsense, straight-shooting, district attorney, Arthur Branch, Fred Thompson was extremely believable as an authority figure and legal expert because he was both of those things in real life. In the 1970s, he served as counsel to U.S. senators during the investigation into President Richard Nixon’s role in the Watergate break-in, and in 1977, he represented Tennessee Parole Board chair Marie Ragghianti in her wrongful termination suit after she stood up to corruption and bribery. In Marie, the 1990 movie about the case, Thompson played himself, the first in a string of big shots in movies like No Way Out, Die Hard 2, and Days of Thunder before he took a break from acting to dabble in Tennessee politics.

In 1994, he was elected to fill out the remainder of an outgoing senator’s term, before serving his own six-year period in 1996. During the final months of his term in 2002, Thompson went back into acting, joining Law & Order. The lawyer-turned-actor-turned-politician-turned-actor then pivoted to politics once more, leaving the show in 2007 to pursue the Republican nomination for president. After a poor showing in early primaries, Thompson dropped out of the race in 2008 and would return to acting a year later, but he never made another Law & Order appearance before his death in 2015.

Michael Moriarty fled to Canada

Like his co-star Fred Thompson, Law & Order cast member Michael Moriarty left a good role on the popular show for political reasons, although Moriarty’s are much more complicated than a run for office. In 1993, U.S. attorney general Janet Reno sought to stop a trend of real-world crime she blamed on TV violence, and she spoke out in favor of legislation that would limit such graphic imagery on the small screen. Acting in good faith, Reno reached out to the TV industry for their input, and she met with Law & Order producer Dick Wolf, as well as Moriarty, who’d played quiet and upstanding District Attorney Benjamin Stone since the show’s inception in 1990.

However, Moriarty was not as retreating as his TV counterpart. He was livid over Reno’s proposals, especially as his show, Law & Order, included very little violence — merely cops and lawyers talking about (and never glorifying) violent acts. Moriarty attempted to counter Reno’s arguments by taking out anti-Reno ads in entertainment industry publications, hoping to build up a network of like-minded professionals. He wasn’t quite able to do that, and, frustrated with the entire American entertainment complex, Moriarty quit Law & Order in 1994, and soon thereafter moved to Canada.

Benjamin Bratt got too big for Law & Order

Certainly one of the biggest breakout stars in the long history of Law & Order and its many successful spinoffs is Benjamin Bratt. After portraying Detective Rey Curtis, a faltering family man with a tendency to lose his temper on suspects, Bratt ended his four-year tenure on the procedural juggernaut in 1999, moving on to a movie career full of commercial and critical hits such as Miss Congeniality, Traffic, Piñero, Despicable Me 2, Coco, and Doctor Strange.

Shortly after his departure, Bratt became just one of five regular Law & Order cast members to earn an Emmy nomination. So how could he leave just when he had a good thing going? Bratt felt, albeit reluctantly, that it was time to go. "After four years I’ve felt like it was time to get back home to my family," Bratt said (via a statement published in the New York Post). Oddly enough, Bratt hadn’t yet started a family when he said he left Law & Order to be with his family, as he married actress Talisa Soto in 2002, and they had their first kid together in 2003. In other words, Bratt’s real reason for leaving the small screen probably had more to do with showing up on the big screen.

Jesse L. Martin had to enter a new stage

For decades, two New York entertainment institutions have provided a way for thousands of local actors to make a living: Broadway and the shot-on-location Law & Order franchise. Many New York actors appear on Law & Order while waiting for their big break on the Great White Way, while for Jesse L. Martin, Broadway led to Law & Order. Following some smaller stage roles in the early ’90s, Martin played HIV-afflicted college professor Tom Collins in the original production of the mega-hit Rent. Then in 1999, Martin joined the cast of Law & Order as junior detective Ed Green, partnering up with Lennie Briscoe (Jerry Orbach) and replacing Rey Curtis (Benjamin Bratt).

But nine years and nearly 200 episodes later, Martin decided it was time to leave TV and return to the theater. "It was pretty much time for me. I need to get back on stage before I get too scared to do it again," he told Entertainment Weekly. "And with that schedule, it would be really difficult for me to ever really get to do anything like that." However, Martin was scheduled to start shooting a Marvin Gaye biopic immediately after he finished Law & Order in the spring of 2008, a project that never came to fruition. In 2010, he got back to Broadway with a role in a production of Shakespeare’s The Merchant of Venice, but he hasn’t left TV behind, as he plays Joe West on The Flash.

George Dzundza didn’t love New York

While it eventually become a well-oiled machine that would run for 20 seasons and hundreds of episodes, it took some time for Law & Order to work out the kinks. While the show’s "law" component included a relatively fresh junior detective partnered with a grizzled senior detective from the get-go, the first pair didn’t work out. Veteran character George Dzundza starred as detective Max Greevey in the show’s first season (alongside Chris Noth as Mike Logan). At the end of that initial slate of episodes, Dzundza started what would become a frequent Law & Order tradition: He left the show because, as it found its voice and procedural format, it strayed from Dzundza’s original notion of the series.

"As the season went on, I saw that the stories were becoming more Dragnet-like," he told Pop Entertainment. "I said no, this is not for me. This is not what I signed on to do. And, I had to take care of my family, frankly, as well." In addition to professional concerns, Dzundza also had personal issues with the show. He was tired of the commute from Los Angeles to the show’s New York City-based production, which is totally understandable.

Leaving Law & Order was just business for Christopher Meloni

There are only a handful of truly classic police pairings in TV history. For example, there’s Crockett and Tubbs of Miami Vice, Cagney and Lacey on Cagney and Lacey, and detectives Olivia Benson and Elliot Stabler of Law and Order: Special Victims Unit. For a long and complicated 12 seasons, these characters portrayed by Mariska Hargitay and Christopher Meloni, respectively, busted dozens of New York City’s worst offenders, until the emotionally-driven Stabler retired off-screen at the beginning of season 13, following his sixth on-the-job shooting.

The reason for Meloni’s departure from SVU, however, was a lot less personal and a lot more business-driven. According to TVLine, contract talks between the actor and producing studio NBC Universal fell apart in the spring of 2011. The parties couldn’t reach a mutually agreeable deal, so Meloni walked, necessitating writers to come up with an exit plan without the actor’s participation.

B.D. Wong was fully awake

A part of Law & Order: SVU since almost the show’s beginning, B.D. Wong joined the series in its second season as Dr. George Huang, an FBI agent/criminal profiler/forensic psychiatrist who was always good for an assist to the NYPD detectives. Wong held the role for 11 years, but he began testing the waters for other projects in 2011 when SVU producers allowed him the time and space to co-star in the pilot for a surreal, psychological police drama called Awake.

After Wong filmed his last episode as Dr. Huang, NBC picked up Awake — with Wong as therapist Dr. Jonathan Lee — as a midseason entry in its 2011-2012 schedule. Rather than pull double duty — a difficult task, what with the long shooting hours of the average TV series — Wong opted to move on and star on Awake only. In terms of long-term employment, Wong may have made a poor choice, as NBC canceled Awake after one season. The actor has returned to SVU occasionally in the years since, with Dr. Huang coming in as an NYPD consultant.

Dean Winters left the fictional police for fictional prison

Before he was Liz Lemon’s sleazy, good-for-nothing, on-again, off-again boyfriend Dennis Duffy on 30 Rock, and before he was the personification of Mayhem in a series of popular Allstate Insurance commercials, Dean Winters was a working actor lucky enough to land roles on NBC’s Law & Order: Special Victims Unit. Winters was a member of the long-running spinoff’s original cast back in 1999, appearing in the first 13 episodes as the very green SVU investigator Brian Cassidy. Halfway through that first season, however, Cassidy disappeared, with the believable explanation that working such grisly, depressing, and harrowing cases proved too much for the detective, and he’d transferred to the narcotics division.

However, the real reason that Winters left was because he was simultaneously portraying inmate Ryan O’Reily on HBO’s Oz, and he couldn’t juggle the roles any longer. "I had to leave because I had a contract with HBO, and there was a bit of a dispute," Winters told The A.V. Club. And so, Winters returned to Oz, but he also came back to SVU in a guest-star capacity several times between 2012 and 2019.

Stephanie March and Raul Esparza went as far as they could go on Law & Order

Law & Order and Law & Order SVU are by definition "police procedural" shows. This means each and every episode follows a tried and true formula in which detectives and lawyers carefully go through the process of investigating, solving, and prosecuting a crime. While that makes for extremely reliable television to the point that even a show about horrific murders can be comforting, it may get a little bit boring for the actors to do essentially the same thing with their character each week for years on end.

And in 2003, after three years of portraying fictional assistant district attorney Alexandra Cabot, actress Stephanie March decided she was ready for something else. "I have zero complaints about Law & Order. It was a fantastic work experience and I really miss the people quite a bit," March told TV Guide in 2004. "But, you know, you get to a point where you feel like, as a character, you kind of said everything you can say. And then it becomes quite redundant."

One of March’s successors, Raul Esparza, who portrayed Assistant D.A. Rafael Barbra from 2012 to 2018, left for similar reasons. "I’ve done six seasons, I felt like it was time to go," Esparza told Entertainment Weekly. "I had explored a lot of what I thought Barba was about."

It was an old problem for Richard Belzer and Dann Florek

Few people have played one character for as long — or as memorably, or on as many different series — as Richard Belzer portrayed Detective John Munch. Belzer and the droll, black-clad Munch will forever be intertwined, what with appearances on Law & Order, Arrested Development, The X-Files, The Wire, and Homicide: Life on the Street, where the character originated. When Homicide ended its run in 1999, producers of the then-new Law & Order: SVU imported the character, where he investigated awful crimes for 17 years. So why would SVU get rid of one of the most famous personalities in TV history? For the sake of realism.

On the screen, Munch retired from his tireless police job, having reached the NYPD’s age limit. "In the real world, which we try very hard to simulate, NYPD has mandatory retirement before your 63rd birthday," SVU showrunner Warren Leight told ScreenerTV. "You can’t have 65-year-old guys running after guys. It is a hard and fast rule." That’s also why Law & Order character-turned-Law & Order: SVU character Captain Donald Cragen (Dann Florek) mostly disappeared after 15 seasons. He’d simply gotten too old for the force.

Danny Pino took too many bites out of crime

Nick Amaro, as portrayed by Danny Pino, was a latter-day addition to Law and Order: SVU, a cop with a tough guy facade that hid an overwhelming amount of empathy. He dutifully partnered up with Mariska Hargitay’s Olivia Benson for five seasons before actor and character moved on. Pino was a solid addition to the cast, as Law & Order: SVU brass knew he was the guy who get the job done. When he joined the show in 2011, he was already a seasoned veteran of police procedurals, having had extended runs on The Shield and Cold Case. And while that experience prepared Pino for Law & Order: SVU, it might also be what led to his exit from SVU (in which Amaro survives a shooting and moves out of New York for a more peaceful life). "Danny did seven years of Cold Case and The Shield and then four years here," SVU showrunner Warren Leight told Entertainment Weekly. "Even last year, he was beginning to want to spread his wings a little."