The man who presided over Queensland's historic corruption inquiry has launched a scathing attack on the Newman government's bikie and sex offender laws.

Tony Fitzgerald QC has warned Queenslanders not to be duped by laws he views as dangerous.

Earlier this month, the government gave itself the power to bypass the courts and keep some sex offenders in jail indefinitely.

Parliament also passed new laws that mean judges must now impose two sentences on criminal bikie gang members who commit a serious crime - one for the crime itself and another for being part of a declared criminal gang.

Mr Fitzgerald says Queenslanders should understand the gravity of the laws, which he warns are likely to fail.