In series 3, Carl briefly worked for the Maguires by growing marijuana for them in his loft, until the police found out about the production. Carl was briefly taken into custody, and gave a statement that the marijuana was grown for the household's own personal use. But after a tip was given to the police about Mandy Maguire (Samantha Siddall) selling weed, her mother Mimi Maguire (Tina Malone) suspected that Carl betrayed them and sent her sons, Donny (Clyve Bonelle) and Shane Maguire (Nicky Evans), after him. Later, Carl's siblings Lip, Ian and Debbie, figured out that the only person with the motive for informing the police about Mandy's dealings was in fact her brother Shane, who was angry that his mother chose his sister over him to oversee that area of the family business. After Lip confronted Shane over the matter, Shane agreed to call off the family hunt for Carl.