Joining an established cast can be a tricky task for some actors. It may take time for the audience to understand and like the new character. Viewers of Law & Order: Special Victims Unit know the drill all too well. Characters have come and gone on more than one occasion.

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During its 23 seasons, the show has seen 15 different ADAs join the squad. ADAs who started on the second season and continue to be loved to this day. Others did not give the viewers the chance to get to know them before they were gone. Whatever the case may be, they all left their mark on the show.

15. Abbie Carmichael (Angie Harmon)

ADA Abbie Carmichael (Angie Harmon) on Law & Order: Special Victims Unit.

Abbie Carmichael was the first ADA the show introduced on its first episode, "Payback." Her appearance on SVU was not long only six episodes but the fans may know her better from her recurring role on Law & Order.

Carmichael is mostly remembered for being the first ADA, but audiences do not feel particularly connected to her. Only watching SVU, there was not much for them to bond with. Her personal story remained a mystery. It is easier to understand her participation in the larger L&O Universe.

14. Mikka Von (Paula Patton)

ADA Mikka Von (Paula Patton) on Law & Order: Special Victims Unit.

As quickly as Mikka Von said hello, she said goodbye. Paula Patton’s appearance was one episode long as she worked with the detectives on “Wet.” She came in like a tornado, trying to do as much as possible in a very short period of time.

A daring ADA, her straightforward and relentless attitude cut her trip short, and she was sent back home to Chicago. However, fans remember her precisely for her attitude. In only 42 minutes, they saw her fight for the victim and try to get justice. Although she could have gone another route, she will be remembered for trying.

13. Michael Cutter (Linus Roache)

ADA Michael Cutter (Linus Roache) on Law & Order: Special Victims Unit.

Michael Cutter is mostly known for his role on Law & Order, so fans were not surprised to see him join the Special Victims Unit squad for four episodes alongside Alexandra Cabot. He brought to SVU the same energy he was known for.

Cutter, just like Jack McCoy, had a tendency to bend the rules when it was necessary for the case. Although at times it may have seemed unethical, fans liked his plans as he would always fight to get a conviction.

12. Sherri West (Francie Swift)

ADA Sherri West (Francie Swift) on Law & Order: Special Victims Unit.

Season 12 of SVU saw three different ADAs come and go. One of them was Sherri West who was introduced during the first part of the season, "Bullseye," and returned for the second half of it.

West’s work getting convictions was remarkable; probably why she returned. However, fans now remember her as the ADA who switched sides. During her last appearance on the show, she had become a Defense Attorney.

11. Gillian Hardwicke (Melissa Sagemiller)

ADA Gillian Hardwicke (Melissa Sagemiller) on Law & Order: Special Victims Unit.

Season 12, Episode 6, “Branded,” gave fans their first look of new ADA Gillian Hardwicke. For ten episodes, she was a badass keeping up with her 92% conviction rate. Although at first she struggled to make room for herself in the team, she succeeded in the end.

Viewers could relate to Hardwicke because she had a bit of a fangirl in her. As she is first introduced, we learn she chose to be transferred to Manhattan because she admired the work Detectives Stabler and Benson had been doing. Just like the fans, she wanted to continue watching them do what they do best: catch the perps.

10. Kim Greylek (Michaela McManus)

ADA Kim Greylek (Michaela McManus) on Law & Order: Special Victims Unit.

Kim Greylek, also known as The Crusader, joined SVU on season 10, episode 1, “Trials,” and stayed on for 22 episodes. She is probably the ADA who had the hardest time adjusting to the squad and making room for herself. From the beginning, she was butting heads with Stabler.

Greylek was originally known by her co-workers as someone who goes the extra mile for the victims she is representing. Hence, the nickname. She was a tough ADA who may not have been liked by everyone, but will surely be remembered by all.

9. Jo Marlowe (Sharon Stone)

ADA Jo Marlowe (Sharon Stone) on Law & Order: Special Victims Unit.

Sharon Stone, who recently joined The Flight Attendant season 2, guest starred on SVU as ADA Jo Marlowe during season 11. Marlowe is probably one of the ADAs audiences know the most about because of her connection to Stabler. She was his older partner.

Although her arch is only four episodes long, viewers enjoyed her participation quite a lot. Her past with Stabler gave plenty to talk about. Particularly with Detective Benson, who was asked by the ADA herself if she had ever crossed the line with her partner. That “no filter” attitude is what captivated fans.

8. Peter Stone (Philip Winchester)

ADA Peter Stone (Philip Winchester) on Law & Order: Special Victims Unit.

Peter Stone came from the One Chicago Universe to create a name for himself. Moving to New York after the death of his father, he joined the squad as ADA during season 19 after Barba’s departure and stayed for 36 episodes.

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Most fans seem to enjoy Stone’s episodes because of his close relationship to Benson’s son, Noah. The ADA spent a lot of time training the kid on baseball which seems to have led to his feelings for the mother. During his last appearance, he reveals he cannot work with her anymore because his feelings for her have pushed him to act in a way he is not comfortable with in his career. Another man under Benson’s spell.

7. David Haden (Harry Connick Jr.)

Olivia Benson (Mariska Hargitay) and ADA David Haden (Harry Connick Jr.) on Law & Order: Special Victims Unit.

Unlike Stone, David Haden succeeded in having a relationship with Olivia Benson as the feelings were reciprocated. However, this relationship, which developed during season 13, could have been extremely problematic for both parties.

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The fans mostly got to know Haden through Benson’s eyes and their relationship. Their secret meetings in donut shops which she accused of being stereotypical are what allowed viewers to see how much he truly cared about his job. Sadly, he was pushed to leave after Paula Foster (Paget Brewster), who reported to him, was caught committing fraud.

6. Elizabeth Donnelly (Judith Light)

ADA Elizabeth Donnelly (Judith Light) on Law & Order: Special Victims Unit.

Nowadays, fans mostly remember Donnelly as the firm, to-the-point judge who had a particular relationship with Detective Stabler based on sarcasm. Before her time on the bench, she was an ADA, and she supervised Alexandra Cabot and Casey Novak during their time.

She had a dry sense of humor, “people, take your meds,” and a straightforward attitude that she tried to pass along to her more rebellious successors. For 25 episodes, she stayed in fans' good graces as an all-time favorite for how well she was able to fit in with the rest of the cast.

5. Sonya Paxton (Christine Lahti)

ADA Sonya Paxton (Christine Lahti) on Law & Order: Special Victims Unit.

Sonya Paxton was the first ADA to bring the sass with her into the squad room. As soon as she walked in, she was immediately butting heads with Detective Stabler and trying to side with Benson. However, the team and audience got a better understanding of her character when her alcoholism was revealed.

Paxton was the kind of character that you either love or hate. Detective Benson had her issues with her at first as she saw a lot of Serena in the ADA. But we see she came to care for Sonya on the episode in which the ADA is murdered. Fans learned how to love this character with each passing episode as her sass and sarcasm grew on everyone.

4. Dominick Carisi Jr. (Peter Scanavino)

ADA Dominick Carisi (Peter Scanavino) on Law & Order: Special Victims Unit.

Dominick “Sonny” Carisi Jr. joined the squad as a detective, but everyone feared it would not be for long as he was done with his law degree. Shadowing Rafael Barba, he later followed in his footsteps as he became an ADA.

The transition from detective to ADA was hard for both the squad and the fans. Seeing Carisi fight some detectives’ actions, which he had done in the past, was troublesome. Although he was still on the same team, he played under different rules. However, he grew into his new role and became one of the top ADAs the show has seen.

3. Casey Novak (Diane Neal)

ADA Casey Novak (Diane Neal) on Law & Order: Special Victims Unit.

Casey Novak was one of the strongest ADAs SVU has ever seen. She joined the team during season 5, and throughout her time kept a 71% conviction rate. Although at first she found it hard to get along with the squad, she ended up becoming one of them and a friend to many.

Fans love Casey Novak for how she sticks to her beliefs and fights to get justice. She has always gone the extra mile, which is why she first left the show with a suspension for crossing the line. Nevertheless, viewers are happy to see her come back for an episode occasionally.

2. Alexandra Cabot (Stephanie March)

ADA Alexandra Cabot (Stephanie March) on Law & Order: Special Victims Unit.

Stephanie March, who recently joined Naomi, is an all-time favorite SVU character. For 97 episodes, she has come and gone many times. First to join the Witness Protection Program, and then to be part of the International Criminal Court after a case that left her shocked.

Alex Cabot was the kind of ADA who used her network and asked for favors from judges when it was extremely necessary. The fans have loved her since the first time she showed up on screen during season two. She is one of the ADA who Benson and Stabler have come to care for and call a friend.

1. Rafael Barba (Raúl Esparza)

ADA Rafael Barba (Raúl Esparza) on Law & Order: Special Victims Unit.

Although Rafael Barba is no longer an ADA, Raúl Esparza was seen during Season 23 as a Defense Attorney. From the moment he joined SVU on season 14, episode 3, “Twenty-Five Acts,” fans knew he would be unlike any previous ADA. He was not afraid to cross the line, letting a suspect choke him with a belt in court.

Barba’s sassiness and sarcasm followed him for 119 episodes, but what truly made the audience love him was his friendship with Olivia Benson. The two found a chemistry that made their scenes memorable. Although at the moment their relationship seems to be over, there is hope Barba will return for another episode and the friendship will resume.

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