The CMA acquired its powers on 1 April 2014 when it took over many of the functions of the Competition Commission (CC) and the Office of Fair Trading (OFT).
The UK Competition Appeal Tribunal (CAT) "is a specialist judicial body with cross-disciplinary expertise in law, economics, business and accountancy whose function is to hear and decide cases involving competition or economic regulatory issues." (Description from CAT's homepage.)
Neutral citation is [yyyy] CAT #