On Friday, thousands of people are expected to rally on the steps of Victoria’s Parliament to campaign for the removal of GST on sanitary products.

The Andrews Labor government supports the removal of GST on sanitary products. There is no sensible reason to charge the GST on these products.

More broadly, the Liberals have kicked off a lot of frenetic and fragmented debates about the GST recently, and the question of removing the impost on sanitary products is just a small part of the discussion.

Tony Abbott and Joe Hockey have been keen to talk up the importance of engaging in tax reform across the country.

In recent weeks, the prime minister indicated that his preferred option was to increase the GST rate from 10% to 15%.

That is not tax reform – that’s just a sham, and it lays the groundwork for another broken promise by the Abbott government.

We do not support increasing the GST to 15%. The GST, by its very nature, is a regressive tax. The people it hits the hardest are those who can least afford it.

The tax has no regard to a person’s capacity to pay. Increasing the rate would mean that those on lower incomes would continue to pay a larger proportion of their incomes than those on higher incomes. It’s the definition of unfair.

That’s why we’ve argued for an increase in the Medicare levy instead, so we can get to work and fix our health system. Victorians deserve world class treatment but it is under pressure from spending cuts and population growth.

An increase in the Medicare levy would not affect those on lower incomes. People with annual taxable incomes of less than around $20,800 do not, and would not, pay the levy at all. Similarly, seniors and pensioners earning less than around $33,000 are exempt.

There are no such exclusions for the GST. Everyone is slugged by it: those that can least afford it, all the way to those for whom its payment barely even constitutes a ripple.

An increase to the Medicare levy would go some way to funding the extra costs associated with the challenges of maintaining and improving the level of health care Victorians expect and deserve.

These are challenges made even more pressing by the Abbott government’s massive cuts in funding to hospitals and schools. The cuts to Victoria’s public hospitals alone are to the tune of $17.7bn over the next 10 years.

In education, the Abbott government’s decision to reverse its commitment to the Gonski funding arrangement meant that Victorians schools were faced with cuts of $8.9bn over the next 10 years.

What these situations desperately illustrate is the need for a mature and informed discussion about what our federation looks like, and how it actually operates. We currently have a federal government that has shown a tendency to shirk its responsibilities and is all too willing to shift them to the states, most evidently in the key areas of education and health. However, this shift has not gone hand in hand with a commensurate source of funding.

Our position on the GST is not up for negotiation, certainly when the Abbott government is unable to keep its current commitments.

The states and territories need certainty of funding to ensure key services continue to be funded, and the GST does not provide that certainty. The GST is not the solution for meeting these responsibilities.

The states are overwhelmingly the provider of the day-to-day services Australians depend on. The commonwealth is good at taxing and lecturing states, but rarely is it part of the solution, a solution that must include greater fiscal autonomy for the states.

Tony Abbott backs Mike Baird's call to raise GST to 15% Read more

The revenue base of the states must not be the budgetary ballast for a poorly run federal budget that has doubled the deficit in two short years and looks set to run deficit budgets with monotonous consistency.

As part of the introduction of the GST in 2000, all states agreed to abolish a number of inefficient state-based taxes. While Victoria led the nation in this regard, several other states have maintained some of these taxes. Despite Victoria meeting its commitments, $1.5bn in GST will be redistributed from it in 2015-16. Any further increase in the GST pool will simply see Victoria subsidise the rest of the federation even more.

If Tony Abbott wants Victoria to help lay the groundwork for another one of his broken promises so he can go to the next election offering the charade of income tax cuts, then we won’t have a bar of it.

Governing is about taking responsibility, not shirking it. Abbott needs to face up to our challenges and find a real solution, because increasing an unfair tax is not the answer.