England's general Teaching Council (GTC) is seeking new powers to suspend teachers from the profession's register while they are under investigation for alleged inappropriate behaviour.
But teaching unions warn that the right to be presumed innocent is being replaced with a presumption of guilt, and the move could worsen the damage to reputations caused by malicious allegations.
The GTC, which is responsible for disciplining England's 430,000 teachers, can already strike off teachers if it finds them guilty of serious offences.
Now, the council has asked the Department for Children, Schools and Families for the power to impose an interim suspension on such teachers, stopping them from teaching until the allegations have been resolved.
Teachers will demand an end to "unnecessary and unreasonable" suspensions at the NASUWT union conference, which starts on Monday in Birmingham. They will also call for the powers of the GTC to be downgraded so that it is merely a regulatory body, along the lines of the British Medical Association.
Chris Keates, the union's general secretary, said most teachers who faced accusations would be suspended from their jobs for the duration of the investigation anyway.
"The GTC is asking for two bites at the cherry," she said. "Where false allegations are rife for teachers, the GTC would be making a bad situation worse."
Alan Meyrick, the GTC's registrar, said it was important for it to be able to suspend teachers when certain cases were referred to it.
"We expect this would only affect a very small number in exceptional and particularly serious cases, where it was considered important in the public interest," he said.
At the Association of Teachers and Lecturers' (ATL) conference in Torquay this week, teachers were urged to work with their local authorities to draw up blacklists of pupils who had maliciously accused staff of attacks or sexual abuse.
Mary Bousted, the ATL general secretary, said that often the first teachers knew of it was when they were called into the headteacher's office and suspended.
"In too many cases, the very fact that the allegation is made is the end of their careers," Dr Bousted said.
Michael Wills, the justice minister, has written to Jim Knight, the schools minister, asking him to consider whether the treatment of teachers who are subject to allegations is consistent with the European Convention on Human Rights.
Mr Knight said that the police needed to crack down on malicious allegations. He agreed to teachers' requests to talk to Home Office ministers about the problem.