Five years after one of the Victorian Parliament's most divisive battles, Premier Denis Napthine has reignited the debate over women's reproductive rights, saying he would consider any attempt by balance-of-power MP Geoff Shaw to overhaul the state's abortion laws.

Dr Napthine, a Catholic who voted against the decriminalisation of abortion in 2008, said he would assess any move by Mr Shaw - or any other MP - to wind back the existing laws on merit. He told The Sunday Age he would allow a conscience vote on the issue, which could lead to a replay of the acrimonious scenes of 2008, when Labor and the Coalition split over the issue internally.

Premier Denis Napthine. Credit:Pat Scala

When the law finally passed after months of emotive debate, advocates of abortion decriminalisation believed the issue had been settled for good.

But in an interview to mark one year from the next election, Dr Napthine did not rule out helping to overhaul state abortion laws. ''There's a number of ways somebody could act to rewrite that legislation and I would make my judgment on the basis of what was proposed,'' he said.