Should all tax returns be available online? Most people’s knee-jerk reaction is that it would be absolutely horrifying for everyone to see what you earn. It’s an entirely private matter between you, your employer and the taxman. It would be a gross intrusion of privacy if it was made available to the public – and worse, to the newspapers.

But these same arguments were used when we were first allowed to see sold house price data. It would be nothing less than a “snoopers charter”, argued some, with nosy curtain-twitchers checking out the silly price the neighbours paid for that dump next door.

Today, hardly anybody thinks it’s intrusive that sold house prices are published all over the internet, except perhaps Tony Blair and family, when we learn they have hoovered up their zillionth buy-to-let property.

If we took the plunge and opened up HM Revenue & Customs to scrutiny, might we get over our ourselves and see the benefit from public disclosure?

In Norway, no one can disguise their earnings, with every tax return made available to anyone in the country to inspect. It’s not just a matter of the prime minister grudgingly forced into disclosing. Workers can see what their colleagues are earning, and neighbours can snoop on how much the people next door are making – all legally, and all available online.

Norwegians say they are intensely relaxed about the figures being made public. This may be because the figures have been published locally for centuries. They see it as a core part of citizenship and a way of showing you are contributing. One said it may also be why the country has a flatter pay structure than we have in Britain.

Trade unions largely support the idea; in private companies with unpublished pay scales, individual pay can be hugely unfair and discriminatory.

Facebook Twitter Pinterest Comedian Jimmy Carr was one of the first to be caught up in tax avoidance. Photograph: Sarah Lee/The Guardian

Would it also help to tackle tax avoidance and evasion? Not necessarily, though transparency always helps. In Norway there is a media feast every year in October when the returns are released. Newspapers can crawl over politicians’ and celebrities’ earnings. The likes of Jimmy Carr would have had a tough time explaining how they managed to avoid paying their fair share of tax. He has been desperately contrite since. But how many other people with extravagant earnings use one fiddle after the next?

A 2001 academic study by the University of Michigan and Statistics Norway into the impact of the country’s decision to open up data on the internet found that the “deterrence effect” prompted a 3% rise in taxes paid by business owners. In a British context, that could add up to billions of pounds.

Oddly enough, the history books tell us that US tax returns were originally made publicly available – until the rich found it embarrassing and got the practice stopped. Economist Timothy Taylor highlights how the Civil War Income Tax Act of 1862, which introduced income tax in the US, meant tax information about individuals was posted on courthouse doors and sometimes published in newspapers. But by 1894 Congress prohibited the public inspection of income tax.

In calling for salary and tax transparency, inevitably some readers will say: “Why don’t you just publish yours, then?” And yes, I will – when we have a situation where you can see mine and I can see yours.

Crucially, in Norway you can see your neighbour’s earnings – but they get an email saying you’ve had a look.

“Each citizen has a personal interest, a pecuniary interest in the tax return of his neighbor. We are members of a great partnership, and it is the right of each to know what every other member is contributing to the partnership and what he is taking from it.”

Those were the words of US president Benjamin Harrison in a speech in 1898. They still hold true today.