Felton is a prison guard of Slabside Maximum Security Prison.
After Oliver stabbed officer B. Dunbar and several other guards at Daniel Brickwell's fight club, as well as expose the fact that Jarrett Parker was lobotomizing the inmates with support from the guards, the federal government sent Felton and several other guards to reform the prison. Felton is one of the new guards who ensures that there is less yard time, cell checks every half hour and that everyone is kept in line, including Dunbar.
After officer Dunbar was stabbed to death multiple times in the showers last night, Felton immediately blamed Stanley Dover for it since Stanley was the last person to see Dunbar alive. Because of this, Felton and two other guards arrived to Stanley's cell to take him down to the hole as punishment for what he has done. Oliver secretly investigated the scene where Dunbar was killed and found Turner's blade at the scene, deducing that Ben Turner killed Dunbar because of Dunbar refusing to work for Brickwell any longer. Oliver informed Felton about this and Felton had the blade examined to find Turner's fingerprints on it. Enraged, Felton had Turner detained in front of the inmates, taken to the hole, and had released Stanley. Felton was unaware of this: he was right the first time, Stanley murdered Dunbar and then planted evidence so Turner would get blamed for the murder.
Later, after the FBI agreed to release Oliver because of a deal that Laurel Lance made with them, Felton arrived to Oliver's cell to inform him of his release while being ungrateful about it. When Oliver realized Ricardo Diaz was in the prison, Oliver tried to warn Felton about Diaz only for Felton to ignore those warnings out of arrogance. When Oliver broke out of his cell to find Diaz, Felton warned him to stand down only for Oliver to refuse. Felton then pulled out his baton to fight Oliver only for Oliver to take him and the other guards out. Angered by Oliver hitting him in the stomach and for disobeying him, Felton told Oliver that he will put an end to his early release. Felton's arrogance cost him dearly when Diaz orchestrated the prison riot and got the inmates to gather the guards. Felton and a guard named Miller were almost killed by the inmates until Oliver and Turner rescued them. After thanking Oliver for saving him and Miller, Felton told him and Turner that some of the guards made it to the panic room and some were taken to the mess hall by Diaz.
After Turner saved all of the guards, he returned to his cell, finding "The Count of Monte Cristo", book left for him by Oliver to read as he did, and acquire hope. Felton approached Turner, whom he helped save from certain death before, and Felton thanked him for saving everyone's lives, leading Turner to contemplate his redemption. Felton's kindness towards Turner made him become a better man than before.
Felton is extremely overconfident, to the point that he believes that Slabside Maximum Security Prison is impenetrable, as he believes that it is impossible for any individual to infiltrate the prison without anyone knowing about it, even when Oliver Queen try to warn him that Ricardo Diaz had escaped from custody, it was only after Diaz began a prison riot that he found out the hard way that Oliver was right. He is also at his core a law-abiding man who keeps the other guards in line, like B. Dunbar.
Unlike Peter Yorke, Felton is well respected by the other guards and never tried to get on both the inmates as well as the guards' nerves for his own amusement. According to Stanley Dover; unlike Yorke, Felton is a professional jerk; due to him ensuring that there is less yard time and cell checks every half hour. Stanley was glad that Felton was around since Felton prevented Daniel Brickwell from harming him, ultimately, Stanley still murdered Dunbar in cold blood at the showers and planted evidence so inmate, Ben Turner would get the blame for it. Felton was consumed with grief and anger when he learned Dunbar was dead. Felton (correctly) deduced Stanley committed the murder and was ruthless enough to arrest him in front of Oliver as well as refer to Stanley as a "little bastard".
Felton is not above displaying respect for inmates who earn it, initially, Felton was annoyed with the FBI for dropping the charges against Oliver for vigilantism, When Oliver and Ben saved Felton, and Officer Miller from certain death, Felton displayed humanity for Oliver and Ben, unlike Peter Yorke, by thanking them as well as trying to warn them about Diaz killing his co-workers in the riot for sport, Felton started respecting Oliver for saving his life, but was unsure of Ben, after the riot was over and Ben helped Oliver save the lives of Felton's remaining co-workers, Felton thanked Ben for his aid similar to Oliver. So as of now, Felton has nothing but respect for Ben and Oliver.