June Stahl

Season one

June Stahl arrives in Charming in episode 6, "AK-51", and is assigned to a case involving the Sons of Anarchy Motorcycle Club and their involvement in inter-state arms trafficking. She had been called in by David Hale, the local police department's Deputy Chief, as he had been struggling to rid the town of the gang due to his superior, Wayne Unser's, corruptness. She soon becomes involved in an affair with David Hale. Jax Teller, SAMCRO's Vice President, witnessed them in a sexual encounter at the police station while breaking Cherry out of lockup. Agent Stahl became even more obsessed with crushing SAMCRO after being severely beaten by Big Otto Delaney, who hit her head into a table as a way to show the club that he did not succumb to her pressure. He also detested her for arresting his wife Luann as a way to force him to become an informant. Her subsequent attempts to recruit Opie Winston caused her to trick Clay Morrow, SAMCRO's President, into believing that Opie had betrayed the Club and the others with whom he murdered Hefferen, a port commissioner. Clay responded by ordering Tig Trager to kill Opie and pin it on the One-Niners street gang. Opie's wife, who was driving his truck, was mistakenly killed instead. This incident caused a rift between Stahl and Deputy Chief Hale, who icily told her at the crime scene, "This blood's on you." She continued in her attempts to bring down SAMCRO until the very end, keeping another member, Bobby Munson, in jail three weeks after the case was dropped and he was a free man. When Bobby asked her why she did that, even though it caused so much sorrow and did not accomplish anything, she says it gave her peace of mind.

In a deleted scene on the Season 1 DVD, she is shown waking up with a naked woman in her bed and telling her she has to go, thus revealing she is bisexual. This is the end of the episode.

Season two

Agent Stahl returned again later in Season Two to investigate the L.O.A.N. and the True IRA. She visits Clay in jail in attempt to get him to turn on the IRA. Although she fails at that, their conversation ultimately provokes a physical confrontation between Jax and Clay. She also visits Jax Teller as well in an attempt to exploit the schism between SAMCRO and the IRA and ends up revealing the IRA's betrayal of SAMCRO to L.O.A.N. Jax declines the offer and instills dread upon Stahl with the revelation of her colleague Josh Kohn's murder.

Stahl was able to prey on Chibs Telford's desire to reunite with his family and the two worked out a deal where if Chibs delivered the True IRA to the ATF, she would rescue his estranged wife and daughter and would grant complete immunity for any crimes to SAMCRO. However, Stahl decided to change the deal (no immunity for SAMCRO) but couldn't convince Chibs to go along with it. She threatened him by saying that she herself would tell the IRA about Chibs' betrayal, but she was still unable to break him.

When Opie found out that his wife, Donna's, death was a result of Stahl making Opie appear to be a snitch, he found her and threatened her at gunpoint. However, he showed mercy and let her live. He took out the empty magazine to his gun and gave it to Stahl. After Opie left, Stahl broke down and started crying.

In the season two finale, Stahl discovers that Ethan Zobelle is an F.B.I. informant and passes the information to Chief Unser, who in turn passes it onto SAMCRO. She continued her sting operation with Edmond Hayes and was able to arrange a meeting between him and his father, Cameron. Cameron secretly told Edmond to kill Stahl, so Edmond convinced Stahl that another meeting would take place and she arranged for only herself to be present. At his home, Edmond retrieved a gun but couldn't bring himself to kill Stahl. Stahl revealed that the ATF knew all along about Cameron's plan and that Edmond's gun was loaded with blanks. Feeling like a fool, Edmond punched Stahl and attempted to escape, but Stahl was able to fire several shots from her sidearm and accidentally killed Edmond. Soon after, Polly Zobelle showed up to say goodbye to Edmond, but instead found his dead body. Before finding Stahl, Gemma Teller appeared in the house, looking to exact revenge on Polly. Gemma killed Polly in self-defense and then discovered Edmond's body and Stahl. After telling Gemma to flee, Stahl tricked Gemma into handling her gun, making it appear that Gemma killed both Polly and Edmond.

After Gemma escaped, Stahl announced over her radio that Gemma had murdered Polly Zobelle and then took Stahl's sidearm to kill Edmond Hayes. However, Edmond's father had been eavesdropping on Stahl's broadcast and ends up killing SAMCRO member Half-Sack and kidnapping Jax's infant son in retaliation.

Season three

At the start of season three, Stahl showed no remorse for the fact that her actions led to the death of Half-Sack and the kidnapping of baby Abel. She was demoted off of the IRA case by the ATF after the events at the end of season 2 but was looking for ways to return to the case. She interrogated Tara regarding the kidnapping and was agitated even though Tara was being truthful in an effort to get law enforcement to assist in the search for Abel. Clay told Stahl that if anything happened to Abel because of her, he will personally kill her, which terrified Stahl inside.

Gemma Teller made a personal deal with Stahl to surrender to the federal authorities, but her heart condition flares, causing her to pass out in the drive way of the SAMCRO clubhouse before she can turn herself in. At the hospital, Stahl informed Gemma that the US Attorney will take away the deal because she didn't turn herself in even though she was incapacitated. Jax took a risky move and secretly made an off-the-record deal with Stahl to give her the True IRA in exchange for Stahl pushing back their upcoming bail hearing, reduced time on their gun charges, and Stahl recanting her statement against Gemma.

Stahl proved to be trustworthy in her deal with Jax when she is able to push back SAMCRO's bail hearing by 10 days so that the bikers can go to Belfast to get Abel back. She supplied a rigged testimony for Gemma to relay to the U.S. Attorney's office, incriminating Agent Tyler in the process. She has been trustworthy because she knows that Jax's knowledge of the California gun-running operation can save her dying career and unlike the rest of her deals she had a lot to lose by breaking.

It is reinforced in season three that Agent Stahl is bisexual as she is shown to be having an intimate relationship with Agent Tyler, the one she incriminated in the statement she gave to Gemma. During an assignment, Stahl shoots Agent Tyler in the throat and sets it up as a drive-by from a Mexican gang. In her statement, she admits their intimate relationship and claims that Agent Tyler had confessed to framing Gemma for the murder of Edmond, thereby exonerating Gemma and holding up her end of the deal. When Gemma finds out about the deal, she threatens to revoke her statement and tell the authorities who really wrote it. Stahl replies that she is already too late, as she has already been exonerated.

In the finale of Season 3, she exposes Jax's deal to the club thinking they would kill him. Her motivation for doing so seems to have been malicious. However, Jax was aware that she could not be trusted and had already informed the other members of the club. This led ultimately to Opie, with the help of Unser, targeting Agent Stahl in retribution for her role in the death of his wife, Donna. During this confrontation Stahl breaks down crying and begs Opie for her life, to which Opie responds, "This is what she felt." He then shoots Stahl in the back of the head with a MAC-10, instantly killing her. After this, Chibs Telford rigged the scene to look like hers, and Jimmy O'Phelan's murders were carried out by the IRA.