A few months ago, I wrote about the unsatisfactory and arbitrary ways in which justice is served – or not served – in particular, in cases where the seriousness of the outcome is more to do with chance than motivation.

Those thoughts were prompted by the case of Anne Sacoolas, the wife of an American diplomat who killed a young man called Harry Dunn with her car in Northamptonshire, then left for the US, and refuses to return to face trial. The fact that she isn’t facing a court made it impossible to judge that issue, so instead I asked why the same offence – in this case, allegedly careless or reckless driving – should receive minor penalties when no harm ensues, and potentially a very serious one (14 years in jail), when the worst happens.

The conclusion must be that the law is pragmatic and worldly, rather than dealing with abstract ethical questions. The moral issue raised by careless driving is the same whether or not there’s an accident, but real-world effects are hugely different. But if we accept this compromise – and the very existence of diplomatic immunity is an example of putting practical interests above pure justice – we’re at least entitled to an explanation of why the normal rule of law is being set aside.

The allegation that Mrs Sacoolas is not only the wife of an American diplomat, but herself a CIA agent, doesn’t change this basic dilemma but, if true, goes some way to explaining why this should have been a thorny case in terms of Realpolitik and international relations. The case of Mike Lynch, a British businessman who is to be extradited to America on fraud charges, is a further example of what looks like political expediency winning out over justice.

In 2015, the Crown Prosecution Service found no grounds for prosecuting Dr Lynch, who was running a UK company listed on the London Stock Exchange, governed by English law and UK accounting practices. A subsequent civil case has finished hearing evidence but not yet produced a ruling.

Yet under the US/UK extradition arrangements introduced by Tony Blair’s government in 2003, the Home Secretary “must” process the request, and no appeal is possible. Americans, by contrast, get to challenge such requests from the UK in their own courts, or, in the case of Mrs Sacoolas, ignore them altogether.

This not only seems obviously unjust, it isn’t even very pragmatic in political terms. Even if the UK (like every other country) is less powerful than the US, it cannot be remotely in our interests to allow such one-sided agreements. There may be an argument, even if it’s not very moral one, for compromises for the sake of some supposed greater good. There isn’t for just being kicked around. It may be worth bearing this in mind as we attempt to negotiate a trade deal.