[[folder:The Sheriff's Department]]
!!Sheriff Ralph Lamb (Dennis Quaid)
* AloofBigBrother: To Jack.
* CowboyCop: Literally.
* GoodIsNotNice: He's not hesitant about expressing his dislike for people or his refusal to suffer fools but he is most often the one who suggests doing the right thing.
* GrinOfAudacity: Ralph's trademark grin in his job.
* NiceHat: He, his brother, and his son all wear cowboy hats, fittingly enough.
* OverprotectiveDad: To Dixon.
* SiblingTeam: With Jack.
!!Deputy Jack Lamb (Jason O'Mara)
* DatingCatwoman: Well, he would like to be dating Mia. Both Ralph and Mia are warning him of the potential repercussions.
* DudeWheresMyRespect: Jack feels that Ralph is taking him for granted and not giving him the respect he deserves.
* HiredToHuntYourself: Played with. [[spoiler: Jack, who killed Johnny Rizzo, volunteers to lead the investigation.]]
* ParentalSubstitute: He raised Dixon when Ralph served as a military policeman.
* SiblingTeam: With Ralph.
!!Deputy Dixon Lamb (Taylor Handley)
* BornDetective: Katherine notes that he's got a knack for detective work. He even impresses Savino in "Estinto".
* TheCasanova: He is a big hit with the ladies and in his EstablishingCharacterMoment he is trying to get away from an angry husband firing a shotgun.
* DudeWheresMyRespect: See Jack's entry.
* [[WhyDidItHaveToBeSnakes Why Did It Have To Be Spiders?]]: He hates this. The other deputies tease him for it. Ralph tells Jack that he was really raised on a ranch.
!!Yvonne Sanchez (Aimee Garcia)
* GirlFriday: While she is the sheriff department's receptionist, she also helps out with investigations.
* SpicyLatina: Averted. She's too all-American to be one and she's not particularly HotBlooded.
* TwoferTokenMinority: Mexican and female.
!!Assistant District Attorney Katherine O'Connell (Carrie-Anne Moss)
* BadassDamsel: She outwits a rapist long enough for the cavalry to arrive in "Masquerade".
* ChildhoodFriend: She grew up on the ranch next to the Lambs.
* NervesOfSteel: In "Masquerade", Ralph notes that it's the first time he's ever seen her not in control.
!!District Attorney Rich Reynolds (Michael Reilly Burke)
* CorruptPolitician: He's working with the mob and feeding them information about cases relevant to them, as well as selling out the previous sheriff.
!!Mayor Ted Bennett (Michael O'Neill)
* RetiredBadass: He is a former army officer.
[[folder:The Chicago Mob]]
!!Vincent Savino (Michael Chiklis)
* AffablyEvil: Extremely polite to everyone, loves his family and friends, [[BreadEggsMilkSquick orders the car bombing of a snitch...]]
* BenevolentBoss: Is friends with most of his men and gives advice to his casino employees on how to get better tips. He even allows some employees who were stealing money from the casino to leave without incident. However...
** BadBoss: ...if a mobster or employee does something he ''really'' doesn't like (such as beat up an employee for information without orders to do so) and he may beat the crap out of them. And if they get arrested for murder and stealing money from his casino and threaten to turn information over to the DA? Then they are screwed.
* EvenEvilHasLovedOnes: He cares a lot about his wife and daughters and gets very upset when [[spoiler:Borelli]] is killed by a Milwaukee mob hitman.
* EvenEvilHasStandards: He dislikes it when civilians get caught in the crossfire during mob confrontations, does not tolerate narcotic use in his operation, goes out of his way to get an innocent employee away from Rizzo's wrath, and [[CrowningMomentOfAwesome "teaches some manners"]] to a group of young motorcycle punks that threaten a family who gave Vincent and his [[ThoseTwoGuys "associates"]] a ride when the trio was stranded.
* NiceToTheWaiter: Very much so. He gives his workers pointers on how to get better tips and saves one poor waiter from a fellow mobster with a HairTriggerTemper. Vincent also went off his way to give to beatdown to Beansy after he witnesses him attacking a casino dealer after informing Vincent in locating the corrupt Clark County Sheriff since he didn't give the order to beat the dealer.
* UglyGuyHotWife: With Laura.
* VillainousFriendship: With Red, Mia, and Borelli. Not so much Beansy because he is a moron.
* VisionaryVillain: He sees Las Vegas as the next big thing for the mob and is pushing his bosses hard for expansion of operations in the city.
!!Anthony "Red" Cervelli (James Russo)
* VillainousFriendship: With Vincent.
!!Mia Rizzo (Sarah Jones)
* DefrostingIceQueen: It's subtle, but she's slowly warming up to Jack.
* EvilGenius: She's the casino's count room manager and is responsible for the monetary take to give Savino's mob family in Chicago.
* MissingMom: There's no mention of Mia's mother and it's obvious that she's out of the picture since Mia's dad gets engaged to Diane.
** [[spoiler: It's later revealed that Lena Rizzo is still alive and is trying to reconnect with her daughter]].
* NervesOfSteel: She remains remarkably cool under pressure and has got a hell of a poker face.
* VillainousFriendship: With Vincent.
!!Nick "Beansy" Cota (Sonny Marinelli)
* ThoseTwoBadGuys: With Vic.
!!Vic Borelli (Joe Sabatino)
* AffablyEvil: In "The Real Thing", he was polite enough to give a truck driver some money and tell him that he won't be killed to make sure he gets home to his family after hijacking his cargo truck.
* [[spoiler:KilledOffForReal: By Jones in "Bad Seeds".]]
* ThoseTwoBadGuys: With Beansy.
!!Laura Savino (Vinessa Shaw)
* ExactWords: She tells ADA Katherine O'Connell that she will never tell Katherine anything that might incriminate her husband and his associates. The next time she talks to Katherine, she repeats this statement but omits the part about "his associates". Katherine quickly picks up on this omission and the two women reach an unspoken understanding.
* HiddenDepths: She's incredibly savvy when it comes to politics and has even worked for Kennedy's campaign. She puts these skills to use by helping turn Grady's campaign around in "The Real Thing" and "Bad Seeds".
* UglyGuyHotWife: With Vincent.
* [[spoiler:BoomHeadshot: Courtesty of Johnny Rizzo.]]
!!Johnny Rizzo (Michael Wiseman)
* [[spoiler:TheDon: After killing Angelo.]]
* TheDragon: To Angelo.
* [[spoiler: KilledOffForReal]]
* ParentWithNewParamour: He gets engages to Diane in "Estinto". [[spoiler: It didn't last very long.]]
* [[spoiler:TheStarscream: He gets permission to kill Angelo for getting too soft and takes over as the new head of the Family.]]