Medicare co-payments look set to be a key issue for voters in the by-election in Kevin Rudd’s former seat of Griffith in south Brisbane.

The battle for Kevin Rudd’s vacated seat of Griffith will be the first chance voters will to speak out against the Abbott government, Bill Shorten says.

The opposition leader was in the ex-prime minister’s former electorate with Labor candidate Terri Butler to meet voters and to campaign against a government proposal to introduce Medicare co-payments.

The recommendation, from the government’s commission of audit, would mean patients would pay a $6 fee every time they visited their GP.

Medicare co-payments look set to be a key issue in the contest between Ms Butler and her coalition rival, former Australian Medical Association president Bill Glasson.

Mr Shorten indicated other shadow ministers, as well as Mr Rudd, would be visiting the Brisbane-based electorate to help Ms Butler’s campaign on the issue.

“This is the first chance since the election for any Australians anywhere to say to Tony Abbott: ‘stop breaking promises, stop the secrecy… don’t mess with our health system’,” Mr Shorten said.

Ms Butler said voters were unhappy with the new government, which would help her cause.

Meanwhile, disability advocate groups have expressed outrage on social media over a photo showing Mr Glasson’s campaign team blocking a disabled parking spot.

The picture shows a supporter in a Bill Glasson shirt and a corflute banner displaying the candidate’s face in the spot. Mr Shorten said he was reluctant to politicise the issue.

“The Labor party, with my leadership, we’re not going to get into the negative of campaigning,” he said.

“No one should ever park in someone with a disability’s car park.”