Is it likely the Facebook UK CEO will be able to tell them anything useful?
The UK Parliament can decide it has jurisdiction over whatever it likes. You're right that they won't be able to enforce it. But the question Zuckerberg has to ask himself is whether his testimony or his failure to appear will make MPs more predisposed against him and Facebook. Whether or not it's a good idea to snub a parliamentary inquiry in any given country will vary greatly, but generally it will at least be a good idea to give it some serious thought before turning them down.
The British Parliament is an institution that helped shape and construct the present international order, at one point holding jurisdiction over a quarter of the Earth's surface area.
Yeah, this guy is a US citizen, but he is the officer in charge of a multinational corporation that does business in and draws revenue from the UK and its dependents. Is he legally obligated to show up? Probably not. Would Parliament be able to enforce their decision if they decided he was legally obliged? Probably not, not in the case where they come up against the US though if he were resident in nearly any other country in the world though, they probably could.
International law relies on conventions agreed upon by nation-states, themselves a hodgepodge of various domestic and foreign interests. The only really big enforcement actor in the space is the United States Military, and so in cases where the United States Military isn't willing to take action for domestic reasons, international law basically means nothing.
So while Zuckerberg may not have to go himself, he probably should or just cut business ties with anybody in the UK now. They may not be able to force him by military might, but they can make his life difficult and Facebook's continued operations in the UK very very difficult.
Oh and do note that Facebook hosts British data globally, even if operations are conducted locally. In their position I would be going after the parent company, not the local stub unless I had to make a few examples out of the local stub to get the parent company's attention.
There's no international law that prevents the UK parliament - or anyone else - from declaring they wish any random person to appear before them.
I can do that too if I want.
Specific attempts at enforcing it may or may not have legal basis, but that's an entirely separate issue.
It's entirely up to Zuckerberg whether or not he decided to appear, but he will need to consider that if he doesn't he might find the UK parliament more likely to take actions that will hurt Facebook later on.
Unlike Parliament you're not bound by international conventions; though you may be bound like them (for the moment) by EU law.
The ECHR for example puts restrictions on impositions in to the private life of individuals. A demand to appear before Parliament without proper jurisdiction would appear a priori to be such an infringement.
Suggestions that "well Parliament can make things very difficult for him" whilst probably true should be given utmost contempt. Parliament should uphold the Rule of Law and not threaten people, even if it can.
I can't see any reason not to simply demand an officer of Facebook with executive powers be in attendance. Perhaps specified to be the person with management responsibility for data protection.
FWIW I'm very far from being a supporter of Zuckerberg, though am a user of Facebook.
Asking someone to show up is not an "imposition into the private life of individuals".
You call it a demand, and seem to believe it has some kind of legal force, but it does not. They're asking. They're asking firmly, but they're still just asking. It has no more legal force than if I were to ask.
> Suggestions that "well Parliament can make things very difficult for him" whilst probably true should be given utmost contempt. Parliament should uphold the Rule of Law and not threaten people, even if it can.
Parliament is the source of law in the UK. The way parliament can make things difficult for him is to make law. Nobody is suggesting they should threaten people, but it is their job to e.g. consider the impact of how businesses threat their users and if appropriate to pass laws regulating it. If Facebook when given an opportunity to present their side to parliament decides not to take that opportunity, they should not be surprised if such laws does not take their views into account.
Zuckerberg should be happy to be explicitly given the opportunity to present Facebook's side - they need not extend that courtesy. They could instead simply make their decisions without hearing Facebooks side of the story at all.
> I can't see any reason not to simply demand an officer of Facebook with executive powers be in attendance. Perhaps specified to be the person with management responsibility for data protection.
A very simple reason is that they may not believe said persons would be able to offer the same input.
The UK Parliament can decide it has jurisdiction over whatever it likes. You're right that they won't be able to enforce it. But the question Zuckerberg has to ask himself is whether his testimony or his failure to appear will make MPs more predisposed against him and Facebook. Whether or not it's a good idea to snub a parliamentary inquiry in any given country will vary greatly, but generally it will at least be a good idea to give it some serious thought before turning them down.