Despite Voight's reputation as a suspected dirty cop and for using underhanded methods, he commands his unit's loyalty and respect.

However, he has a well-documented feud with Casey—as a result of what happened between them—and his interactions with the firefighters of 51 are marked by tension and suspicion, despite the fact that he earns their grudging respect for his dedication in seeking justice for crime victims.

As the result of Justin's recklessness, the boy (Mike Duffy) who was in the van is paralyzed from the waist down, stopping him from playing hockey ever again.

First beginning with bribery (a new television set for the CFD) and escalating to physical threats towards Casey and his then-fiancé, Dr. Hallie Thomas.

Voight attempted to have Casey injured or killed, but was arrested by Detective Antonio Dawson (Jon Seda) in a sting.

[9] While in prison he offers Gabriela Dawson (Monica Raymund) information on who shot Antonio, who was working undercover at the time.

Voight began working with Dawson and Detective Juiliet "Jules" Willhite (Melissa Sagemiller) to investigate a series of murders relating to pharmacy nurses.

Working alongside Dawson and Detective Erin Lindsay (Sophia Bush), Voight uses firefighter Joe Cruz's brother, Leon, who had former ties to the gang, as part of a sting.

However, despite his ruthlessness and his morally ambiguous and underhanded approach to police work, Voight is a veteran who is determined in getting the job done, is extremely dedicated to the victims of his cases, goes out of his way to protect and help vulnerable young people, and does have his fellow cops' and Chicago's best interests at heart.

It is revealed that he is working with Internal Affairs using his dirty cop reputation as part of an operation to bring down heavy hitters in Chicago's crime world.

More recently, Justin was involved as an accessory to the murder of a rival gang member by his corrupt friend Joe Catalano.

At the end, he gives Justin the ring that formerly belong to his mother (that was stolen in the robbery but recovered) and encourages him to propose to Olive.

Hank is friends with the 21st District's Desk Sergeant Trudy Platt (Amy Morton), and has a decent working relationship with District Commander Ron Perry (Robert Ray Wisdom), who had "six hundred reasons why he didn't want [Voight] to run Intelligence, but one reason why"[14]—because he got results.

In "The Three Gs", after working on the human trafficking case, he threatens the officer that filed an official complaint against Sean Roman.

[15] In "Daydream Believer", he threatens to beat serial killer Greg Yates (Dallas Roberts) to death after he kidnaps and murders Nadia Decotis (Stella Maeve), Intelligence's civilian administrator, and when he saw the crime scene of his two victims in the apartment building.

[16] At the end of "There's My Girl", he demotes Kevin Atwater following an IAB investigation after he leaves a soda can with the suspect that leads to his suicide and promotes Officer Kim Burgess to replace him.

In "Grasping for Salvation", a gun that was used in the murder of a boy was connected to a 17-year-old case that he and his old partner Detective (now Lieutenant) Denny Woods had solved.

In "Monster", he suspects that Ruzek was being a mole when Halstead gets investigated by Internal Affairs and when he asks Platt about the missing money.

Denny Woods reveals that a supermarket was breaking ground on the old railroad property by a bridge but it was halted when builders found some human remains.

Woods says the crime lab is working overtime to clear Voight's name in any wrongdoing and he has brought in the FBI and all hands on deck after everything Hank has been through.

In "Homecoming", Voight goes to Wood's home to broker a deal by confessing to the Bingham murder in order to get Olinsky, with ASA James Osha, there in person.

Voight accused him of screwing Olinsky by prosecuting his case, before storming into the jail director's office the next morning and giving him an even angrier tirade.

Upon finding out who the killer was, by a corrupt corrections officer, Voight beat him up in a storage closet and left him bleeding, claiming the man had tried to attack him.

Though Voight was asked, by Alvin's wife, not to show up at his best friend's memorial, he did make it possible for Meredith Olinsky to collect her husband's pension.

In "The Forgotten", his distrust towards Kelton grows more from "Trust" when he shut down the investigation of a serial killer that resulted the death of his longtime informant.

In "What Could Have Been", he lets Ray Price take the fall for his wife when she killed Burgess's boyfriend and a reverend to protect her daughter.

In "Reckoning", Platt informs Voight, Ruzek, and Dawson that Internal Affairs had taken over the investigation as Kelton's way of trying to take down his unit.

At the end, though Kelton wins the election and becomes Mayor-elect, he is found shot dead that night in his own home and Voight is seen driving away from the scene.

Further investigation into a former CPD cop that was laid off a year ago and died of a heart attack two weeks prior to Kelton's murder soon gives Voight the real killer.

With Kelton dead and his plans for the Mayor's office buried with him, Voight and his Intelligence Unit are able to remain a part of the Chicago Police Department instead of being disbanded.