Sir Thomas Mark Horner, PC (born 1956) is a Northern Irish barrister and judge.
He has been a Lord Justice of Appeal for Northern Ireland since 2022.
[1] Horner was called to the Northern Irish bar in 1979 and became a Queen's Counsel in 1996.
He was appointed to the High Court of Northern Ireland in 2012, receiving the customary knighthood.
[2] He is husband to Karin Horner and father to two children, Katie and Matthew.