In December 2024 he was found guilty of the violent gang rape of a student in Bordeaux in 2017 and sentenced to 14 years in prison.
[1] Born in Dublin, Coulson was part of the St Michael's College side that won the 2012 Leinster Schools Rugby Senior Cup.
[4][5] In August 2017, Irish Pro14 side Connacht announced that they had signed Coulson ahead of the 2017–2018 season.
He retired from professional rugby in 2020 and returned to Ireland, playing for Bective Rangers under former Grenoble coach, Bernard Jackman.
[9] In 2017 Coulson, along with 2 of his teammates at FC Grenoble, was accused of gang rape of an unconscious student.