Anyone with compassion reading this week’s tax avoidance story must feel immensely sorry for David Cameron.

The Prime Minister claimed yesterday morning that he had not benefited from any money that his father may have saved through offshore tax accounts. No inheritance for the young David? His dad must have been a right bastard. Perhaps Ian Cameron – who amassed his fortune of £10m, some of it through placing his money in the Bahamas to reduce his tax bill – didn’t spend a penny on his son. The Prime Minister must have put himself through Eton on a really big paper round.

It’s no wonder that he insists the country must be careful with money, after he spent his youth pleading, “Dad, can I have 80 pence for my bus fare to the Bullingdon Club ball where we squirt cat sick at midgets?” and was told “No you bloody well can’t. If you want your own money, set up a trust in the Virgin Isles.”

You can tell how embarrassed the Prime Minister is about his dad’s behaviour, because he said his dad’s finances were a “private matter”. After all, his dad was a private man; so private, that is, he even kept his finances private from the British tax office.

David Cameron admits he did have a stake in father's offshore investment fund after Panama Papers leak

The Prime Minister was quite clear at first that he had not, and will not “in the future”, benefit from any offshore trusts. And that, after all, is a much fairer way of assessing behaviour than the old-fashioned method our legal system is based on, which concerns itself solely with the past.

With this approach, a defendant could reply to the question “Did you break through a wall and rob Hatton Garden?” by saying “Look, I’ve been through this several times and let’s be absolutely clear, I stand to gain nothing from robbing any jewellery stores in the future.” And off they’d go.

It’s touching to see our Prime Minister defend his father, even after admitting he had, in fact, benefited from his income. Hopefully if Jeremy Corbyn asks him any questions about him, Cameron will reply: “I’ll tell you what my father would have said – ‘do your tie up, sing the National Anthem, and spirit millions of quid away in the Bahamas so none of it gets taken and used for frivolities like treating cancer’.”

You can’t blame anyone for the actions of their parents, and that must be why the Daily Mail, as a sensitive family newspaper, isn’t making a big fuss about this issue. It’s true they declared Ed Miliband’s dad was “The man who hated Britain” - but that was a matter of national security, as he’d fought for Britain in the war, proving he was prepared to take up arms which could have proved lethal if he came back to life and then became a Jihadist. But Cameron had simply tried to help out our overworked tax clerks, by leaving them with small numbers to add up rather than big complicated ones that can take all day.

George Osborne was even clearer about whether he benefited from tax avoidance schemes, saying: “As I’ve said, all of our interests as ministers and MPs are declared in the register of members’ interests and we’ve made our position very clear,”

So he was asked again, and replied: “As I said this Conservative government has done more that any Labour government or any previous government to tackle tax evasion.”

If he was asked again he’d probably say: “I told you already, I never go cycling on an empty stomach.” And then: “Look, how many more times? Beenie Man is my favourite dancehall reggae artist. Now I have an important meeting to attend. Good day.”

David Cameron's biggest controversies Show all 8 1 /8 David Cameron's biggest controversies David Cameron's biggest controversies Pig-gate A book released by Conservative peer Lord Ashcroft alleged that an MP and Oxford contemporary of David Cameron had allegedly seen a photograph of Mr Cameron performing a sex act on a pig while at university. Downing Street did not comment on the allegations and the peer said they could have been a case of mistaken identity David Hartley/REX Shutterstock David Cameron's biggest controversies ‘Swarm’ of migrants In July 2015 David Cameron referred to refugees coming into Europe from the Middle East and North Africa as a “swarm”. He was criticised for using the language, which critics said was dehumanising Getty David Cameron's biggest controversies Child tax credits In April 2015 David Cameron was asked whether he’d cut child tax credits. “No, I don’t want to do that,” he said, saying that he rejected reports that he would. Shortly after the election the Government unveiled cuts to child tax credits EPA David Cameron's biggest controversies Cycling to work As leader of the opposition David Cameron was regularly photographed cycling to work. In early 2006 he was photographed cycling but with a driver in a car carrying his belongings. It was suggested at the time the cycling was just for show and that having two vehicles on the road instead of one was wasteful Rex David Cameron's biggest controversies Andy Coulson David Cameron employed former News of the World editor Andy Coulson as government communications director from 2010. After stepping down from the post due to coverage of the phone hacking affairs, Mr Coulson was later found guilty of conspiracy to intercept voicemails. He served a short prison sentence AFP David Cameron's biggest controversies His personal windmill Early in his leadership of the Conservative David Cameron made an effort to change the party’s image by making eco-friendly gesures. As one of these gestures, the future PM put a wind turbine on his house. However, the turbine later had to be removed after neighbours condemned it as an eyesore and the council’s planning committee said it had been put in the wrong place Getty David Cameron's biggest controversies Funeral selfie David Cameron was pictured posing for a ‘selfie’ with Danish PM Helle Thorning-Schmidt and Barack Obama at Nelson Mandela’s funeral. Some in the press criticised the prime minister for showing in an inappropriately low level of respect for the gravity of the occasion AFP/Getty Images David Cameron's biggest controversies Eating a hotdog with a knife and fork The Prime Minister was pictured eating a hotdog with a knife and fork in the run up to the 2015 general election. He was accused of being “posh”. “I had a very privileged upbringing... I've never tried to hide that,” he said Reuters

Everyone connected with these trusts insists they’ve ‘done nothing illegal’. It’s a refreshing attitude, as you can get fed up with people worrying whether someone’s behaviour breaches any code of morality. Presumably, if the wife of one of these businessmen came home to find them having an orgy with the entire cast of Emmerdale in a room mocked up to look like Anne Frank’s attic, they’d say, “Alright, don’t make a fuss. I’ve not done anything illegal.”

In a modern world, it’s far more appropriate if wealthy people can decide how much their tax bill comes to, rather than be constrained by the stuffy old system of being told by the government how much to pay. Maybe we can extend this rule to other items, such as cheese. If you can afford it, register a cheeseboard in the Cayman Islands and then you’re allowed to take as much cheese as you like for four pence a year.

And before anyone gets preachy, as many people have pointed out, we all do it. Grandparents buy their grandchildren an ice cream knowing that, if they kept that money, there might be inheritance tax to pay on it when they die. Is this any different from setting up a series of offshore businesses to channel £50m into Guernsey to avoid contributing towards dialysis machines, so you can spend the money on getting Beyonce to perform live for your daughter’s birthday party?