Any MOT tester is allowed to conduct a QC check on a fellow MOT tester. DVSA do advise appointing your most senior MOT Tester as your quality controller, however this is just advice and not mandatory, and you (the AE) are responsible for employing and managing a robust quality assurance process.

You are not allowed to QC check a tester on a vehicle class that you are not qualified to test yourself. For example, if you are qualified only to test vehicle classes 4&7, you are not allowed to QC a tester who is testing a class 1 vehicle.

Only individuals that hold a valid MOT Testing licence and that comply with the requirements for annual training and assessments are permitted to carry out a QC check. For example, a tester that has been suspended from testing (either for not completing their annual training and/or assessment on time, or not carrying out an MOT for at least 6 months) is not permitted to conduct a QC check.

Site Managers that do not hold a valid MOT Testing licence are not allowed to conduct QC checks.

If your quality assurance system involves a third-party person coming to your site and conducting QC checks, you must be certain that this person is a qualified MOT tester, otherwise your QC records may be invalidated and put you at risk of a disciplinary during a VE visit.