It is revealed through the series that Tom was put up for adoption as a baby and spent most of his youth in care homes. His partially Irish Catholic family viewed him as a mistake and initially shunned his attempts to reconcile, leaing him heartbroken.
Like Stan, Tom is a kind-hearted officer who is friendly with most people on the estate and never takes his job too seriously. He was initially attracted to fellow officer Carrie and was the one who discovered Carrie's false identity. However, he later moved on, even turning down Carrie's offer of sex to keep quiet about her identity fraud. Tom also turned down advances from Mandy Maguire due to his relationship with Debbie Gallagher.
When PC Carrie Rogers joined Tom and Stan as their partner, the pair were clearly attracted to her and vied for her attention. Tom in particular seemed to persue her and the two developed a closer relationship compared to that of Stan and Carrie.
Rather quickly Stan and Tom realized that despite her physical beauty, Carrie was less than delicate. Her dedication to the law and the police force, which she later described as being her life, was extreme and often misguided.
Anyone she even remotely suspected of having commited a crime, no matter how minor, she subjected to violence with Tom and Stan having to hold her back. Carrie didn't just look down on the Chatsworth residents but also Tom and Stan who often faced criticism and insults from her despite the fact the three shared a flat together.
Because of her forceful personality, any attraction Tom and Stan felt quickly lessened (though never disapeared completely in Tom's case) and Tom was always the first to stand up to Carrie.
After a while on the estate, Tom entered a controversial relationship with teenager Debbie Gallagher, who was 15 in contrast to Tom's age of 26 at the time. Debbie was the one who asked him out and the pair began a sexual relationship, that they were forced to keep a secret.
After being arrested by Carrie, who had received a tip that she was selling drugs by a rival family, Mandy became close to Tom. She discovered a letter had dropped which was a reply from his biological family informing him that his birth mother was dead and they viewed him as a mistake of her youth and didn't want to see him. Tom was upset by the letter and told Mandy the story of his youth which he spent in care homes, never being adopted. Mandy became attracted to Tom and tried to ease his sadness by hiring a local actress to play a friend of his mother's however this deception didn't work and Tom told Mandy that he had a girlfriend.
Debbie felt guilty about Tom turning Mandy down so told her about their relationship out of obligation, but Mandy was infuriated, with Debbie stating that she was just jealous. Monica over heard Debbie and Mandy arguing about Tom and informed the rest of the Gallaghers of the relationship. Debbie's brothers were quick to let their disaprovel be known but Tom was invited to dinner with the family and welcomed into the fold.
While walking home from a date one night with Debbie, Tom went to urinate in bushes, only to find he'd actually urinated over a battered and bruised rape victim lying there. Tom called the police, with Debbie leaving before their arrival to avoid awkward questions but Tom was arrested on suspicion of rape because the confused and disoriented victim identified him and due to the fact his DNA was all over her in the form of his urine. Although Debbie could have testified for him, that would only have worsened the situation due to the added charge for his relationship with a minor, so he packed his bags and made plans to flee to Ireland. Before he could do so however, he was cleared of the rape through DNA evidence.
At the beginning of Series 6, Tom was still keen to keep his relationship with Debbie as secret as possible and went on to make a series of embarrassing mistakes as a result, such as pretending not to know Debbie in front of Yvonne and Paddy who were both well-aware. Debbie became frustrated with Tom's clumsy demeanour and began demanding more from him, telling Tom that she was bored of him already.
At Debbie's 16th birthday party at The Jockey, Tom surprised Debbie by presenting her with a key to a new flat that he'd just put a deposit on, but Debbie was less than excited and told him she didn't want to move in with him, before running out of the pub. Tom went after her, but she announced that their relationship was over and that she no longer wanted to be with him.
Tom was saddened and accepting at first, but later turned up at the Gallagher's house in tears, and screamed at Debbie to open her window. Frank went outside instead, having been kept awake by newborn Stella as well as Tom's shouting, but Tom pulled a gun on him and tried to force his way in. Frank, unusually nonplussed by the gun, slapped Tom in the face instead. A franctic, distressed Tom then turned the gun on himself and threatened to commit suicide, but Frank went on to deliver a ferociously brutal verbal attack on him, screaming in his face that he would piss on Tom's grave every day forever if he ruined Debbie's life by killing himself in her backyard. A shaken Tom handed the gun to Frank and was escorted home by Stan.
Alienation and Depature
Afterwards, Tom began to stalk Debbie, sitting in his police car watching her walk to school with friends, and also finding wayward excuses to come to her house. He told Carrie that Debbie was the one stalking him however, and while Debbie didn't want to know Tom, it is unclear whether Tom was intentionally stalking her or just seeing her by chance. The Gallagher household quickly turned against Tom, viewing him as a creep and letting him know this whenever they saw him.
Stan decided to try and cheer Tom up by pulling pranks on him at work, however this started a chain reaction of back-and-forth pranks which resulted in a seemingly more severe joke. Tom phoned Stan in a frantic call for help but when Stan found him, he appeared to have been hung. Stan fled in terror and appeared to have a nervous break down, resulting in long term sick leave for post traumatic stress disorder. However it transpired that with the help of Yvonne and her children Chesney and Meena, Stan had taken the opportunity of the prank to fake his anguish and get himself on sick leave with the possibility of compensation. Carrie was disgusted with Tom's actions, and though Stan did express worry that Tom could lose his job, Yvonne talked him around.
Tom later broke into Debbie's bedroom to leave a box of chocolates there, stating he wanted to make a grand romatic gesture, however while trying to decide where best to leave them he ended up getting caught by Debbie with a pair of her underwear in his hand. On top of this, Carrie reported him for the prank in exchange for a promotion and transfer to Norfolk, making sure to tell Tom that she thought he and Stan were losers and that they had been holding her back before leaving.
Tom was then forced to attend a disciplinary meeting with the superintendent, but he didn't realize that it was for the prank he pulled on Stan and not breaking into Debbie's room. He then managed to get himself into much further trouble by revealing that he had a relationship with a 15 year old Debbie and had broken into her house and been caught with her underwear.
With disciplinary charges mounting, Tom decided to flee rather than face them and went to meet Stan and explain. Stan was sad to see him go but understood his reasons. Tom also left Debbie a voicemail message to tell her that he still loved her and inform her that he was leaving, but before she had even finished listening to the whole message, Debbie deleted it and threw away a photo of her and Tom together looking sad yet resolute.