Mabon moved into rugby union refereeing at the young age of 12, when a knee injury stalled his progress as a player.[2]
He has refereed in the Scottish Premiership.[2][3]
He has refereed in Scottish National Cup matches.[4][5]
He refereed the U20 1872 Cup match between Glasgow Warriors and Edinburgh Rugby in 2019.[6]
Mabon refereed his first Super 6 match on 23 November 2019 between Southern Knights and Ayrshire Bulls.[7]
He is now part of the SRU Elite Referee Panel.[2]
He has refereed in the Kings of the Sevens tournament.[8]
Mabon refereed in the Dubai Sevens in December 2016.[2]
Mabon has refereed at international level. He took charge of the Rugby Europe Trophy match between Lithuania and Switzerland on 16 November 2019.[9]
Mabon was also the Assistant Referee for the Poland v Netherlands match on 17 November 2018.[10] He has also been Assistant Referee for the Women's Six Nations match between Scotland and Italy in 2019;[11] and the U20 Six Nations match between France and Wales in 2019.[12][13]