Gen Prayut was asked by reporters about the issue before he attended the House session when votes were cast on the no-confidence motion against 10 cabinet ministers.
All the targeted ministers survived the motion.
The promotion query was raised by Move Forward Party (MFP) MP Rangsiman Rome during the censure debate on Friday, the last full day of the four-day session.
Mr Rangsiman accused Gen Prayut, who chairs the Police Commission which oversees the Royal Thai Police (RTP), of allowing intervention in senior police promotions in a practice dating back to Deputy Prime Minister Prawit Wongsuwon’s watch of the RTP while the coup-engineer National Council for Peace and Order was in power, according to the MP.
The case in point, according to the MP, related to the so-called “police tickets” privilege that allegedly led to heavy jockeying for senior posts in the police force. The privilege involved a waiver of some criteria set by the Police Commission, which led to promotions having been offered to undeserving officers.
Mr Rangsiman said a high-ranking police commissioner last year wrote to the national police chief seeking his support for appointments of three senior officers who are not under his direct supervision.
The request trampled on the principle that underpins police promotion, Mr Rangsiman said, questioning why both Gen Prayut and Gen Prawit allowed the malpractice to persist.
Mr Rangsiman added the police commissioner himself has received three promotions since 2018 thanks to the waiver of certain promotion criteria. Despite the matter having been raised in the debate, Gen Prayut declined to respond.