<P> When Jax finds out that Abel is in Belfast (despite Jimmy O'Phellan's diversions), he puts into motion a deal with Agent Stahl to give her Jimmy and the True IRA in Northern California in exchange for her dropping the charges against his mother Gemma and reducing the federal gun charges that SAMCRO has against it . Jax knows all too well that this deal is very dangerous for him because he will be going behind Clay and SAMCRO's backs . In the episode "The Push", Jax asks Tara for help moving black market meds and she agrees . The San Joaquin Sheriffs Department raids the SAMCRO clubhouse based on a tip from Ernest Darby (who saw the deal go down) and Jax feels that Tara is risking too much by being involved with him and the club . He breaks up with her and ends up having sex with Ima, one of the former Cara - Cara pornstars . The next morning Tara walked in on him and Ima . When he sees her later in the day he apologizes for what happened earlier, but she is not interested in listening, because she believed he meant for it to happen to hurt her . She thinks he blames her for Abel's kidnapping . He continues to say it is to protect her, but she doesn't believe him . He, Clay and Tig later pick up Gemma from the hospital to take her to Belfast with them . When they arrive, Jax and the club are stopped by the police and are in danger of being deported back to America . After interrogating the officers it discovered that someone not only called them, but also paid them to deport SAMCRO . Once they reach the clubhouse belonging to the Belfast chapter, Jax meets Maureen and Trinity Ashby . Trinity is Jax's half - sister, although this fact isn't known by either of them yet . There are subtle hints that Jax and Trinity may be attracted to each other . Jax later meets with father Kellan Ashby . Father Kellan explains to Jax that the Real IRA wants to get rid of Jimmy O'Phellan and that they want SAMCRO to do it, because the Real IRA doesn't want to resort to killing one of their own leaders . Father Kellan promises Jax that he will give Abel back if Jax kills Jimmy . </P> <P> In the episode "Turas," when SAMCRO are nearly killed by a bomb hidden in a gun shipment put there by the SAMBEL Sgt . at Arms, Jax has a shell shocked vision of his biological father speaking to him, but it turns out to actually be his stepfather, Clay Morrow . The next day SAMCRO, with the help of Sean Casey, interrogates Liam O'Neill about his connection to Jimmy . O'Neill confesses that he blew up the truck that killed members of the Real IRA and SAMBEL . He also admits that McGee is working for Jimmy . After a shootout with Jimmy and his crew, Jax chases Jimmy but can't get to him in time . He makes it back just in time to watch Clay kill McGee for betraying the club . Later that night, Jax and the club meet with the IRA council to present the evidence that Jimmy has flipped and learns that it will not be he who kills Jimmy . Back at the clubhouse, Jax and Trinity come close to having sex, but Gemma and Maureen walk in on them . Jax learns from his mother that Trinity is his half - sister . He takes it well, even joking that in two more minutes he would have been in Tig's territory . After talking to his mother, he meets with Father Ashby to find out where Abel is . Father Ashby admits that he never planned to give Abel back, because he knew of John Teller's desire to keep Jax out of the life and decided if he couldn't help Jax he could try to help Abel by giving him to a better family to raise him . Jax becomes furious and attacks Ashby, only to be thrown over a table . After Jax threatens to kill Sean Casey at gunpoint, Ashby then finally tells Jax where he can find Abel . However, Ashby tells Jax that if he loves Abel, he will let him go . When Jax finally finds Abel, his emotions and Ashby's advice don't allow him to decide whether to rescue Abel or leave him with his new adoptive family . Gemma is furious that Jax might give up her grandson, and she tells him that Tara is pregnant with a sibling for Abel . Jimmy O'Phelan kills the Irish adoptive parents and takes Abel hostage . After this happens, Jax decides he is done taking his father's manuscript to heart and feels that if he never listened to Ashby, his son wouldn't be that situation . Jax and the Real IRA make a deal with Jimmy to trade Abel for a new hostage, Father Kellan Ashby . Right before leaving Belfast, Jax receives an undisclosed phone call from Tig, which might have been about Tara's abduction . </P> <P> Once Jax and SAMCRO return from Belfast, they begin looking for Tara . The Mayans help in the search because Salazar is a threat to their new heroin operation in Stockton Prison . They find two women dead in the road . One is Salazar's girlfriend and the other is a woman Salazar killed for her car . Jax is worried about Tara's safety and Bobby promises him they will bring her back safely . They discover that Salazar not only has Tara, but has also taken Hale hostage . When Salazar reveals that he will trade Tara for Jax, he is ready and willing . Jax proceeds to get into a fight with Salazar . Salazar runs, only to end up cornered in the hall, where Jax stabs him to death and makes it look like self - defense . Later, he goes with Tara to have an ultrasound to make sure the baby is healthy . Jax later meets with Stahl, who is still determined to see the deal through . In the finale, it is revealed that his deal with Stahl was a club decision, and that he would never rat on his family . When she inevitably reneges on her promise of secrecy, he acts the part knowing she will soon be dead and they will serve light time . In a letter to Gemma, Jax assures her that he is not his father and would never rat on the club . However, Tara reads a letter from Jax's father to his mistress Maureen Ashby, after the club is arrested, which strongly suggests that Gemma and Clay were responsible for John Teller's death . </P> <P> Jax and the other club members are released from prison . He has abdominal scars stemming from a prison stabbing incident involving the Russian mob . Also, Jax's appearance is different . He has cut his hair and trimmed his beard . </P>

Who killed jax dad in sons of anarchy