I haven't tested this yet, but from the looks of it the new KWS system is a little strange. If someone scans you in a system other than the one you are Wanted in, they can see the bounty but your status will stay Clean per that system. So if they want to claim your bounty, they have to attack you and become wanted themselves. I only assume this because after scanning someone with a bounty from another system, they stay clean. So I assume if I were to attack, I would get a bounty for the current system despite enforcing justice for the other system. Although the major factions may have something to do with this.
If anyone has tested otherwise, I would love to know. And I don't mean pre 1.3 mechanics. I'm talking current gameplay.
Yes, that's exactly how it's supposed to work. Even before 1.3 - which only changed that you couldn't instantly pay bounties off.
Look at it this way - you're wanted in Nigeria for a crime you committed there. You flee to the Philippines. There, you haven't committed any crimes. You're Clean in the Philippines, Wanted in Nigeria.
Some bounty hunter comes looking for someone who committed a crime in Nigeria and tracks you down to the Philippines. He establishes he has the right person when he finds you. Now if he attacks you to try to claim the Nigerian bounty, he's committing a crime in the Philippines as long as you stay there. Which means he'll end up Wanted in the Philippines, with his own 7 day bounty.
Anyway, you get the idea. There is no overriding 'galactic authority' who issues bounties. It is individual and independent jurisdictions who issue bounties for crimes committed on their turf. Bounty hunters try to collect on them, and risk becoming criminals in some other jurisdiction themselves - of course a clever bounty hunter might wait until a target is dumb enough to come back to space where they're Wanted, so they can legally attack.