The religion’s governing body in Thailand, the Supreme Sangha Council, can crack down on monk wrongdoing.
https://www.theguardian.com/world/2015/may/15/thailand-buddhist-monks-bad-behaviour-crackdown
What is it doing now and how well?
From https://www.ibcworld.org/home/diaspora/Thailand :
"In Thailand, the Buddhist government (represented by a Buddhist Head of State) recognizes the Sangha Supreme Council (Mahathera Samakhom) as the highest governing body for Buddhism. The Sangha Supreme Council is responsible for overseeing the administration and regulation of the Buddhist monastic community (Sangha) in Thailand. It consists of senior monks from the Theravada tradition and plays a crucial role in maintaining the integrity and standards of Buddhist monastic life in the country. (my italics)
Additionally, the Department of Religious Affairs within the Ministry of Culture oversees Buddhist affairs and works in collaboration with various Buddhist organizations and institutions to promote and support Buddhism in Thailand."
By government recognition and oversight, the SSC appears to be essentially an extension of the government. So presumably where does authority ultimately rest?