The Law Society says the Government could override basic rights with plans to allow instant dismissals of government workers who fail new child abuse screening.
The Vulnerable Children Bill will make the public sector more accountable for protecting children, as well as placing greater restrictions on known and suspected abusers.
It will allow courts to impose Child Harm Prevention Orders, restricting the movement of convicted child offenders and other adults assessed as posing a serious risk to children.
Workers on the Government's payroll who have contact with children, including teachers, will all have to go through identity and police checks to screen out potential abusers.
About 370,000 pubic service workers are expected to be affected.
The chair of the Law Society's family law section, Garry Collin, told Nine to Noon more screening is appropriate but he is worried innocent people could have their employment terminated.
Mr Collin says a vindictive partner could make false allegations of child abuse to an employer and unproven accusations made in the Family Court could affect people's jobs.
He says there is always a balancing act between protecting children and the rights of innocent people.
Employment lawyer Andrew Scott-Howman says the suspicion of being a child abuser is enough to break a worker's career forever.
"If an allegation is made that a teacher is suspected of inappropriate sexual behaviour, if you're a parent would you want your child in that class, even if it's just a suspicion and it comes to nothing and it could have been made maliciously?" he says.