More than three in five education authorities could be breaking the law by failing to notify the profession's standards watchdog when teachers are sacked or leave to avoid dismissal.
Councils are legally required to notify the General Teaching Council for England of teachers who have left as a result of concerns about their competency or conduct. But only around 35 per cent are doing so.
While around 80 per cent of England's 150 education authorities have had some contact with the GTCE, for example seeking guidance on disciplinary matters, only 44 have referred at least one teacher for conduct reasons and only 11 for competency.
Urban unitary authorities appear to be the main culprits, according to Margaret Morgan, chair of the GTCE's professional standards committee.
"There is still a significant number who are not passing on information where a teacher has left their service," she told the council's meeting this week in Sheffield.
Carol Adams, the GTCE's chief executive, told The TES that referral procedures were now well established and that the council would be writing to authorities which are not reporting cases.
Mike Walker, of the National Employers' Organisation for School Teachers, said it had also been advising councils of their duties to report cases to the GTCE.
But he suggested the lack of cases could be because authorities are using competency procedures to improve teachers' performance.
Since the GTCE started its disciplinary work in June 2001, it has handled 79 unacceptable conduct cases and 21 for serious incompetence. Before disciplinary panels were established there was no route for dealing with incompetent teachers who had left one authority to take up work elsewhere.
Forty-three cases have been reported so far. As a result, five teachers were prohibited from teaching and five were suspended. Sixteen were allowed to continue teaching subject to conditions, such as undertaking additional training or not being responsible for children of a particular age. Ten were reprimanded and seven were either cleared, given no sanction, or their cases were outside the GTCE's jurisdiction.
Ms Adams defended the GTCE's record on dealing with teachers who have appeared before its panels. Recent high-profile cases have included a teacher who was imprisoned for keeping an illegal cache of guns but allowed to return to the classroom.
Last week, a design and technology teacher, who was convicted and jailed for punching and scarring a man in a pub brawl, learned that he can carry on teaching.
The GTCE issued a two-year conditional registration on James Bashford, who works at Chosen Hill school, Gloucester, requiring his headteacher to provide sixmonthly reports on his conduct.
In the past week there have been another two hearings (see below).
Ms Adams said: "Sanctions have been taken against nearly every person who has come before the GTCE.
"The council is using a range of sanctions, for example teachers are made to undergo training or have to report back to the council when they take a new job so we can monitor where they are working.
"Individuals may be doing a really good job of teaching and have already had their punishment for whatever their crime was. The council issues these sanctions but does not have a blanket policy of keeping people out of teaching.
"The important thing (to ask) is what are the restrictions and conditions on their teaching."