Foreign Minister Julie Bishop said this week: "We remain committed to seeking justice for the victims of MH17. We have attributed state responsibility to Russia." And US Secretary of State Mike Pompeo said: "We need the Russians to continue to be held accountable for that."

So perhaps Australia (and the Netherlands, Malaysia and Britain, for that matter) should make it clear that when Vladimir Putin sets foot on US soil (at the astonishing invitation of Donald Trump), we will seek his extradition to Australia to stand trial for the murder, or at least the manslaughter, of the 38 Australians who were on-board the Malaysian Airlines flight when it was shot down in 2014 over eastern Ukraine by separatists supplied with Russian weapons.

In 2002, the Australian Parliament passed the Criminal Code Amendment (Offences Against Australians) Act. It says: "A person is guilty of an offence if the person engages in conduct outside Australia; and the conduct causes the death of ... an Australian citizen or a resident of Australia; and the first-mentioned person intends to cause, or is reckless as to causing, the death of the Australian citizen or resident of Australia. Penalty: imprisonment for life."

There is also a manslaughter offence punishable by 25 years.

So when Bishop says we "have attributed state responsibility to Russia", she really means Putin. In the words of Louis XIV of France: "The state? I am the state." In modern Russia, Putin is the state.

For extradition, the United States needs to have similar laws, and several US states do define offences against US citizens abroad in a similar way.

If we are serious about seeking justice, our intelligence agencies and police should gather the evidence with the help of international agencies and charge Putin with murder or manslaughter.

As lawyer Geoffrey Robinson has pointed out, attaching accountability and culpability to individuals rather than just nation states can be very effective.

The sanctions against individual Russian oligarchs is biting. They cannot enjoy their ill-gotten gains outside Russia. Directing personal responsibility to Putin also has merit. As with individuals and the criminal law, it creates a deterrent. Putin should know he is a prisoner in his own land.

On the other hand, a Putin state visit to the US would be tantamount to an exoneration and be an insult to the families of Australian victims.

It would be no good to try to stop the visit by an appeal to Trump's better instincts because he has none. Rather we have to put pressure on Putin's baser instincts: protecting himself from arrest.

Britain has evidence that Putin directed some if not all of 14 murders of Russian-connected people on British soil.

Australia, Britain and others should make it clear that the moment Putin steps foot in a liberal democratic nation he will be arrested.

(On this subject, I wrote last weekthat one of the victims in Britain had been poisoned by "plutonium". It was in fact polonium.)

Treasurer Scott Morrison has assumed that he can change the way GST money is distributed to the states. The Coalition's political antenna tells it that Western Australia is a crucial part of its base and that Western Australians see GST distribution as a major issue, in a way that residents of other states do not.

This is because, under the original formula, GST division has had a large impact on WA. The mining boom gave WA a lot of royalties in which the other states or federal government did not share, and they counted in the GST repatriation formula. WA's distribution shrank to only about 40 per cent of the GST that was raised in WA.

Unfair, WA cried, after squandering the mining boom money rather than putting it away for when it would inevitably affect its GST distribution.

Enter Morrison. Under his remit, each state would get back from the Commonwealth at least 70 per cent of the GST raised in their state, rising to 75 per cent down the track.

The legality of the Commonwealth doing this unilaterally is suspect, to say the least.

The 1999 GST law says the distribution must be made according to the principles of the awkwardly named horizonal fiscal equalisation. Under those principles, Australians, in whatever state or territory they reside, should have equal access to governmental services. Capacity to raise revenue (such as mining royalties) and disabilities (such as distances, isolation, low population density, high indigenous population etc) are all weighed up when carving up the GST.

The ability of a federal treasurer to unilaterally change that formula will invite a High Court challenge.

Moreover, a challenging state could well argue that there is a binding contract here. After all, the states agreed to abandon some taxes (such as the deposits and withdrawal taxes, and wholesale sales tax) as part of the arrangement.

Recall that, during the Howard government, every time Labor put up a scare campaign that the Coalition would increase the GST, the government's response was that that could not happen without the concurrence of all of the states and territories that were part of the original agreement.

Similarly, you could argue that changing the distribution mix cannot happen without the same concurrence.

All that said, it is doubtful that a contract between the states and feds could prevent the feds from legislating contrary to that contract. The constitution gives the Commonwealth exclusive power to raise excise taxes, and the GST is an excise. The Commonwealth could legislate to increase the GST, widen its base or change the formula for its redistribution without the states and territories agreeing. But given the 1999 GST law, it is hard to see how the Commonwealth could change any of those things without new legislation.

So if Morrison cannot get the agreement of all states and territories (and good luck with that) or does not legislate, which means Senate concurrence (and good luck with that), his new GST redistribution plans are likely to founder on the rock of one or more state challenges in the High Court.

crispinhull.com.au