Greens MLC Tammy Franks wants state laws changed to stop any male charged with murder from using a defence of a panicked response to an unwanted homosexual advance.
The South Australian Legislative Councillor said the so-called gay-panic defence could potentially be used to have a murder charge downgraded to manslaughter.
Ms Franks said she understood the defence had not been called on in SA, but said the law was archaic and already had been abolished in other states.
"This is a defence for somebody charged with murder to downgrade their charge. In 2013 it's not ordinary for an unwanted homosexual non-violent act to be considered worthy of somebody's life having been taken for that charge not to be murder," she said.