Ridicule is the most potent weapon in politics. Labor’s Bill Shorten greeted Treasurer Joe Hockey’s talk of income tax cuts being on his election agenda with a guffaw.

“When Joe Hockey talks about a tax cut you have to start putting your hand over your wallet,” he said.

For mockery to work, of course, there has to be a kernel of truth in the joke. The evidence against the Treasurer and this government is compelling.

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After promising no new taxes or increases and to leave the GST unchanged, Mr Hockey has done the exact opposite.

In the government’s first budget it whacked an extra two per cent tax on anyone earning above $180,000. It has restored indexation to the petrol tax. Just last week it hit purchases on the internet with the full 10 per cent GST. And the government has unsuccessfully tried to impose a GP tax three times.

Mr Hockey has done all this because reality bit the day he took over the Treasury reins. The magic pudding of no tax increases and no cuts while at the same time addressing the “budget emergency” was always unsustainable.

Now we have the Treasurer returning to this election-winning concoction. He has attacked the one measure that was responsible for 80 per cent of his revenue growth in the 2015 budget – bracket creep.

Bill Shorten: not impressed with Mr Hockey’s tax plans.

He is outraged at the idea that left unchecked, 300,000 Australians will move into the second-highest tax bracket in the next two years as their wages rise.

Heroically he says he doesn’t accept the view that we can sit idly by and allow bracket creep to cover rising government spending. He argues that by cutting taxes from the top down will boost confidence and the economy. The idea is more people paying lower tax is better than fewer people paying higher tax. Never mind that the fewer people are the very high income earners.

The Treasurer does accept that spending will have to be trimmed. While there is no longer talk of a budget emergency he is still talking of returning the budget to surplus.

An accountant at his Sydney tax cuts speech asked if he would tell the electorate clearly where government funding is to be cut so people will know what they are voting on. He gave a confident one-word answer: “Yes.”

He and his Prime Minister were badly burnt by their 2014 budget for not only breaking promises but also for unfairly hitting low- and middle-income earners.

The first real test will come in the Canning by-election. It’s hard not to conclude the timing of the speech and that September moment of truth are related.

Nobody, despite his assurance to come clean before the general election, is expecting Mr Hockey to spell out how he will pay for the tax cuts before the by-election. He was adamant on Sky News that while there will be some tax cuts, there will be some tax changes in other areas. That can only mean tax increases elsewhere. We’ll have to wait to find out where.

Maybe it means saving the budget billions, as identified by the Australia Institute, by being far less generous with high-end superannuation tax concessions and a raft of capital gains tax exemptions.

Don’t count on any of that. And be wary of yet another tax cut promise.

Paul Bongiorno AM is a veteran of the Canberra Press Gallery, with 40 years’ experience covering Australian politics. He is Contributing Editor for Network Ten, appears on Radio National Breakfast and writes a weekly column on national affairs for The New Daily. He tweets at @PaulBongiorno

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