One of the issues at the trial was the matter of jurisdiction - basically, whose laws were the Pitcairners breaking, which courts had the authority to try them, etc.
My question is, if the Pitcairners were a sovereign nation (and there was no ambiguity about this point), would there have been a precedent for holding them accountable for their actions (in this case, sexual abuse against children), in some other court somewhere, anyway? IOW, if it were discovered in some small microstate, say San Marino for example, that the locals were sexually abusing children with impunity and there were no laws against it, would the Italian government (or perhaps the European Union) want a word?
Are there other examples, throughout history, of citizens of small nations being held criminally liable for their actions in the courts of other nations?
The ultimate court of appeal in international law is the battlefield. If a country’s laws allow something that other countries consider sufficiently heinous, and a peaceful agreement can’t be reached to change the laws, then the other countries will fight a war to change the situation. Consider that in Nazi Germany, it was legal to systematically murder Jews.
A) WWII would not have happened just because the Germans were murdering Jews.
B) Systematically murdering Jews (or anyone else) was not legal; the fact that it was happening was an open secret, but still against extant German law.
Absent a war, not really. The Nuremberg trials were ostensibly about punishing war criminals but there were plenty of noncombatants tried for various crimes - a woman who falsified evidence against her husband to get him sent to the front lines (and subsequently killed) was convicted; however, none of the jurists could agree on whether or not that was a “crime against nature”, ie. sufficiently heinous to warrant the idea that some universal law existed that she was guilty of breaking, so they sentenced her to a lesser charge based on a preexisting law passed by the Weimar government.
Based on your examples, in other words, no - unless it was a crime in the country that you committed the act in and they simply failed to punish you for it.
Under the Alien Tort Claims Act, a Pitcairn victim could possibly bring a civil suit for money damages against a Pitcairn assailant in US federal court. However, the Pitcairn assailant would have to be in the US to be served with process (the legal papers) at the outset of the suit, and the court would likely have to find that the assaults constituted a violation of the victim’s human rights under international law. The Act has no analogous criminal provisions.
The US also has some laws allowing for the prosecution of a US citizen for criminal acts that the citizen commits overseas (such as traveling to a foreign country and engaging in sex with a miner). But those laws would not apply to non-citizens committing such acts outside the US.
To further expound on this, the courts of a given state (nation-state) may assert three types of jurisdiction:
Personal, ie. US courts may try a US citizen for a crime regardless of where the crime took place; similarly, US courts may try a foreign national for a crime committed against a US citizen in a foreign locale, depending on applicable treaties;
Territorial - US courts may try anyone for a crime committed on US soil, assuming they can, which is to say if the accused is no longer on US soil, they would first have to be extradited;
Subject matter - this doesn’t apply too much under international law; the only example I can think of would be a military tribunal or admiralty court asserting jurisdiction over a deserter who renounces his citizenship.
As you’ll see, none of the above allow a state to assert jurisdiction based on pure moral grounds. Even personal jurisdiction is limited to a given court/state’s ability to project its jurisdiction. The Pan-Am/Lockerbie bombing is a good example: Scottish courts had personal and territorial jurisdiction; US courts had personal jurisdiction and territorial jurisdiction (since the crime was committed on a US aircraft); courts of any number of countries could have asserted personal jurisdiction; and, IIRC, US courts also had subject matter jurisdiction due to various agreements governing international air travel. Libya, of course, had personal jurisdiction since the bombers were Libyan citizens, but refused to try them.
That’s a very sarcastic answer, and one which is not at all in accord with the current standard of established international law. Nations have renounced the jus ad bellum; fighting a war is not something which is at the discretion of nations any more. Which does not mean that countries may not resort to the use of violence under any circumstances; the right to self-defense is the prime example. But you can’t invoke self-defense to fight a war simply because you think another country should ban a behaviour which it hasn’t banned so far. There are scholars arguing that the “humanitarian intervention” can also be invoked to justify violence, but this is far from being established.
It’s also true, as others have said, that in many countries, the courts claim jurisdiction for trying offences committed abroad. This is typically the case if the offender or the victim is a ctizen of that other country. Actually enforcing such a judgment is a totally different thing. If the country where the offender resides refuses to extradite or punish him, there’s hardly anything you can do. The same goes for enforcing a judgment passed in a civil lawsuit.
It’s a bit easier with a civil suit, since you can seize their assets rather than having to seize an actual person. Of course, if they have no assets in your country, that’s no help at all.