I am the Law

I have a problem with Paladin's move: I am the law. Is the paladin can use it to interrogate prisoners, or incite someone to believe in what he says?

The first one is certainly true, though you'll have to be creative in interpreting the choices.
The second one is a good point to start asking questions about what "divine authority" is and what kind of orders can the Paladin give.

I don't think I understand the problem. Can you restate it?

Ie #1: Paladin go to lords house and tell:

I am Paladin of Blablabla, give me your money!

Ie #2: Paladun interrogate a prisoner:

In the name of Blablabla, tell me all what you know!

Ie #3:

I am Paladin og Blablabla, we really did this (killed a Dragon, where not), accept this as true.

Those situations trigger "I am the Law"?

In the way it is written the order must be a direct action to a deity's tenents, the Paladin can't just speak any order he wants, telling someone to give them their money could be fitting, if said person stole it / acquired it from illegal sources / is not sharing it when he/she should.

It is very open ended, but fleshing out the god will give the power more definition, giving an order usually means defining a course of action too, so not just stating "facts". If they try to use it on a prisoner, for example, I would not use the move, falling to parley instead, the base of the order is not his divine authority, in this case, it is the fact that he is ordering someone who is trapped / locked / imprisoned.

Okay I'll play.

"I am Augustine of the Holy Order of the Pristine Crown. By the divine authority of Pelinore, God of Mercy and Justice, I demand you hand over you're ill gotten loot!"

I roll a 12. What's your move?

Depends on the fiction, noclue.

If we're talking about some poor shmuck who knows he can't win a fight, yeah, he's not going to fight. However, trying to get away through the crowd seems like a pretty decent option.

Now maybe this happens in court? Confronting some powerful corrupt duke or something. Running is out, it'll make him look guilty. He's not going to do as you say. So he'll attack, but in a way befitting the situation. He'll use words, his position, etc. against you. "Attack" doesn't always mean swords and arrows.

Ie #1: Paladin go to lords house and tell:

I am Paladin of Blablabla, give me your money!

Who's the deity? What authority are they claiming? The god of taxation? Sure, they'll hand over their taxes. The god of theft? They'll probably attack, though maybe not with weapons.

Ie #2: Paladun interrogate a prisoner:

In the name of Blablabla, tell me all what you know!

Who's the deity? What authority are they claiming? Who's being interrogated?

If they roll a hit the choices are of course relative to the situation. Doing as you say is obvious, and attacking probably is, but fleeing when they can't physically move isn't so obvious. It probably means retreating within their mind. I'd say something like "you see a moment of comprehension, as he realizes just how screwed he is, and then his eyes go kind of blank. His stare goes right through you. It's like he's trying to mentally escape the situation; he's probably thinking about a mug of ale and a nice bed or something."

Ie #3:

I am Paladin og Blablabla, we really did this (killed a Dragon, where not), accept this as true.

Who's the deity? What authority are they claiming? What's the situation?

If this is the paladin trying to show off then the NPC will probably just go with it. Accepting it as true doesn't mean they're friendly though. I think most NPCs would probably go "Okay, fine, you slayed it! Good for you, jeez"

If the truth is going to be problematic for the NPC then they might flee or attack, as relevant to the situation. Fleeing in a noncombat situation isn't a big deal; an NPC can easily just throw his hands up and leave. Attacking might be trying to disprove the statement or arguing.

Ie #1: Paladin go to lords house and tell:

I am Paladin of Blablabla, give me your money!

Said like that? No.

Also; a lord would have friends within the local religious authorities; even if the Paladin worded it better ("By the power of the god of XYZ and in the name of their most holy temple, you are hear-by convoked to bring forth the material wealth of this Household in aid of a righteous and ordained cause.") the lord would delay/make excuses/flat out lie and pay lip service to placate (social equivalent of fleeing) or aquiese and then go complain to the paladin's superiors (the social equivalent of an attack). Complaining to the paladin's superiors is a big one; part of "Being the Law" means that you must function within the law, and are too subject to the law.

All in all: not very Paladin-like, in general, and even if it is, it will have social consequences.

Ie #2: Paladin interrogate a prisoner:

In the name of Blablabla, tell me all what you know!

This is much more stable footing, and probably quite accurate. Most weak-willed people would indeed fold to the Paladin's demands; the Paladin has the weight of an entire military-religious organisation behind him, plus wields the power of a god like a weapon. He has presence, inspires awe and dread.

Ie #3:

I am Paladin of Blablabla, we really did this (killed a Dragon, where not), accept this as true.

This would be abuse of the Paladin's organisation and defamation of their divine authority. It may very well work. But ultimately, news will get back, people will find out the paladin is a fraud, and not only will it destroy his reputation, it will also weaken the influence of his organisation and cast a poor light on the religion as a whole.

A paladin acting in such a way, especially in the first and third examples, is asking to be branded a heretic, hunted down and beheaded by a loyal paladin.

Depends on the fiction, noclue.

If we're talking about some poor shmuck who knows he can't win a fight, yeah, he's not going to fight. However, trying to get away through the crowd seems like a pretty decent option.

Now maybe this happens in court? Confronting some powerful corrupt duke or something. Running is out, it'll make him look guilty. He's not going to do as you say. So he'll attack, but in a way befitting the situation. He'll use words, his position, etc. against you. "Attack" doesn't always mean swords and arrows.

Exactly!