Cllr Mordey was appointed as Leader of Sunderland City Council in 2024. He was first elected to the Council to represent Hendon ward in 2008. Prior to becoming Leader, Cllr Mordey held a number of positions, including Cabinet Member for City Services and Deputy Leader of the Council.
He represents the Council and city on a number of bodies and organisations, including the North East Combined Authority, where he is portfolio holder for Finance and Investment and Chair of the Finance and Investment Board. He's also a member of the Key Cities group executive as portfolio holder for Finance, Infrastructure and Investment.
Cllr Mordey was appointed to the Board of Governors in 2025 in the position of Local Authority Representative on the Board.