(CNN) -- Mike Coughlan, the Formula One engineer suspended for two years in 2007 following the "spygate" scandal, has apologized for his actions after returning to the grid with Williams.
Coughlan was working for McLaren when he was found to be in possession of confidential documents belonging to rivals Ferrari.
The revelation led to his expulsion from the sport, a fine for the team, and the loss of all their constructors' championship points.
However, last month, Coughlan was named chief engineer of the Williams team and he has told the official Formula One website that he is determined to make amends for his actions four years ago.
Coughlan said: "What happened was life-changing because it made me reflect upon myself and my actions.
"Leaving a team and a sport that I love, and then seeing the consequences of my actions on the team and its fans was devastating.
"All I can do now is work hard and try to earn my place back in Formula One. This is what I am determined to do with Williams."
He continued: "I would like to take this opportunity to apologize to everyone who was affected by my conduct and in particular the people at McLaren and Ferrari and the fans of those teams.
"I sincerely regret my actions and I fully accepted the penalty given to me by the FIA. I can only hope that I can earn back everyone's respect."
Williams used to be one of the biggest teams in Formula One, but have been in decline for several years.
They have not won a grand prix since 2004 and currently lie ninth of the 12 teams on the grid, with just four points from seven races.