Tutuola was raised in Harlem (although he claims to have been born in Brooklyn) and was six during the 1968 riots following the Martin Luther King, Jr. assassination, making his birth year 1962. He served in the United States Army, where he saw combat in Mogadishu. Fin has a stellar combat record, and was awarded the Combat Cross.
A former narcotics detective, Tutuola joins the SVU squad in the episode “Wrong Is Right“, as a replacement for Monique Jeffries (Michelle Hurd). He is then paired with Det. John Munch (Richard Belzer).
While in the Narcotics Division, Tutuola worked undercover regularly. He would often spend weeks or even months at a time in various alternate identities. He left Narcotics and transferred to SVU when his partner took a bullet that was meant for him.
Tutuola initially has a rocky relationship with his colleagues in SVU, especially with Munch and Olivia Benson (Mariska Hargitay). Unlike them, he sees the world in black-and-white, with all criminals equally deserving of prison regardless of extenuating circumstances. He also keeps a tight rein on his emotions, refusing to talk about his problems or to admit that the grisly nature of his work often affects him. For example, he and Munch are partners for nearly a year before he opens up about his former partner’s death. Subsequent episodes reveal that he has a distant relationship with his gay son, Ken.
In the season 9 episode “Undercover”, both he and Benson go to Seaview Prison to investigate a case, getting there in time to save Benson from being raped. In Season 9 finale “Cold”, Detective Elliot Stabler (Christopher Meloni) suspects that Fin tipped off temporary partner Chester Lake (Adam Beach) before he and Benson could take Lake into custody. Stabler checks Tutuola’s phones, infuriating him. Near the end of the episode, Stabler apologizes for not trusting him, but Tutuola dismisses his apology because he believes Stabler will always be the same “rat-bastard” tomorrow. Afterwards, he requests a transfer from the squad.
However, three months later (as revealed in the season 10 episode “Trials“), Tutuola’s transfer request had become bogged down in red tape, keeping him with SVU. As Captain Don Cragen (Dann Florek) explains it, the person in charge of transfer paperwork is a colleague of Tutuola’s in the narcotics unit who holds a grudge because his ex-wife started calling Tutuola after their divorce. Hearing this, Tutuola resigns himself to the likelihood that his transfer will not be effected anytime soon. No further mention of Tutuola’s transfer request is made after this point. Tutuola’s relationship with Stabler also seems to have warmed again since then.