A 23-year-old student got six months for stealing a £3.50 case of water from a supermarket.

A 43-year-old man is in jail pending sentence for stealing items worth £1 from a newsagent.

But, if Jack Straw is right and we need more prisons, he should be one of the first inmates, alongside Tony Blair, who he served so loyally throughout the 13 years of New Labour government.

Jack Straw was foreign secretary during the run up to the Iraq war in 2002-3. He was, the Iraq Inquiry tells us, the only member of Tony Blair's cabinet to be fully informed of the prime minister’s discussions, negotiations and plans.

Straw knew that when George Bush and Tony Blair met at Bush's Texas ranch in April 2002, they "signed in blood" a secret deal to invade Iraq, whatever the views of the United Nations or the people of the United States and Britain.

Just prior to that meeting, Straw told Blair in a secret memo that "legally there are two potential elephant traps". Firstly, that "regime change per se is no justification for military action". And secondly, that "the weight of legal advice here is that a fresh mandate may well be required".

And it was Straw who was central in the attempt to bounce the United Nations into that second resolution to give a fig-leaf of legality to a war of unjustified aggression. He was rarely off our screens in 2002 telling us how Iraq was not giving access to the UN weapons inspectors, knowing that this simply was not true, as Hans Blix the chief UN inspector has pointed out, noting Straw's "incorrect answers"—better known as lies—to the Iraq Inquiry.

And Straw knew it was a lie when on 11 February 2003, a few days before the biggest anti-war demonstration in British history, he said: "We have to strain every sinew, even at this late stage, to avoid war."

Straw had already told Blair in his March 2002 memo that the US was going to war regardless, and later he was left in no doubt by the US secretary of state Colin Powell in March 2003, who told him, "We are going to war whatever Saddam does."

The only sinew Straw was straining was to find a way to justify a war which was going to happen regardless of legality or whether most countries and most people in the world opposed it.

This is why he rejected the advice of his senior legal advisor at the Foreign and Commonwealth Office (FCO), Sir Michael Wood, who told him in a memo that invading Iraq "would amount to the crime of aggression" and would be illegal under international law. It was the only time in Wood's career, before or since, that his legal advice had not been accepted by a minister. http://news.bbc.co.uk/1/hi/8479996.stm

And this is why Straw was dismissive of Sir Michael's deputy FCO, Elizabeth Wilmshurst, who stated in her letter of resignation in March 2003, " I cannot agree that it is lawful to use force against Iraq without a second Security Council resolution."

Yet, despite all this evidence to the contrary, Jack Straw told the Iraq Inquiry that he would never "have been a party" to a war of regime change, which he said would be "improper and self-evidently unlawful".

Straw is clearly a congenital liar whose ability to speak untruths is limitless. But he knew what would be the consequences of the war on Iraq, legal or not, because he described them in February 2003:

People will get killed and injured. That is the brutal and inevitable reality of war. Some of those killed will be innocent civilians; even those killed who are not innocent have souls, and wives, husbands, children who will suffer.

Straw knew he had it in his power stop this illegal war. In a written statement to the Iraq Inquiry in January 2010, he said he was "fully aware" that, as foreign secretary, his support for military action would be "critical" if the UK join the invasion of Iraq. "If I had refused that, the UK's participation in the military action would not have been possible. there would almost certainly have been no majority in cabinet or in the Commons."

This is tantamount to a confession that he colluded in mass murder. Not only would Britain have been unable to march "shoulder to shoulder" into the illegal war, but the inevitable resignation of Tony Blair and the fall of his government would have put enormous political pressure on the United States for at the least a postponement of its war plans.

The blood on Straw's hands is no less than that of Tony Blair, for a war in which over one million Iraqis died, four million were made homeless and the country so devastated that today there is acute rationing of electricity, many areas have no access to clean water and a health service that was once the most developed in the region is in tatters.

So next time we hear David Cameron talk about "criminality pure and simple" and he tells "the lawless minority... you will pay for what you have done" we need to know if his definition of "criminality" extends beyond the crime of stealing a £3.50 bottle of water or receiving a pair of stolen running shorts.

Does it include what the the Nürnberg Tribunal, set up after World War II, following the trials of leading Nazis, called the supreme international crime:

To initiate a war of aggression ... is not only an international crime; it is the supreme international crime differing only from other war crimes in that it contains within itself the accumulated evil of the whole.

The Tribunal said individuals should be held accountable for "crimes against peace", defined as the "planning, preparation, initiation or waging of a war of aggression", which leaves little doubt about incrimination in the mass slaughter and devastation inflicted on Iraq by Jack Straw and his fellow conspirators—from Tony Blair, George Bush, and Colin Powell, to Dick Cheney, Condoleezza Rice and Donald Rumseld.

Jack Straw's enthusiasm for jailing people predates his call on David Cameron to build more prisons to lock up rioters. The Blair years were marked by a doubling of the prison population to over 80,000, giving Britain the dubious accolade of locking up more of its citizens than any other European country. When Jack Straw became home secretary, he was ever hungry for more prison places.

It tell us much about the quality of justice in this country that the person in charge of building new prisons was someone who should have been incarcerated in one of the cells.