1. What would trigger your character enough to do something mechanically?
Any visible event where I think I can truly affect the outcome of that event through mechanics (and am not dependent on a scripted outcome solely influenced by the other party) and which is not stupid nor wasteful for my character to attempt. I must be able to notice and affect the trigger offered by the other party.
The devil is not in the 'what', there are laundry lists of actions that would trigger Merdaneth to take action. It is more a question of *how* the person executes said trigger. Let me give a few examples:
Example 1
Somebody post he's aiding slaves to escape from their masters in the Empire, but there are no independently verifiable actions made in-game to support his claim (he doesn't perform any in-game actions to support his claim).
Result: I do nothing.
Example 2
Somebody post he's aiding slaves to escape from their masters in the Empire, and he is actually moving slaves from the Empire to another place, but he isn't doing it himself and isn't telling me who he's (alt or third party) using.
Result: I do nothing.
Example 3
Somebody post he's aiding slaves to escape from their masters in the Empire, and he is actually moving slaves from the Empire to another place, and he is using alts or third parties.
Result: I contact those parties and try to verify the story. If they admit to it, I might threaten them with a war-dec if that's feasible (they are not hauling in an NPC corp and aren't part of a big alliance for example)
Example 4
Somebody post he's aiding slaves to escape from their masters in the Empire, and he is actually moving slaves from the Empire to another place, and he is doing it himself.
Result: I contact him and might threaten him with a war dec if he does not desist. I gather intel by using locator agents and other sources to try and find out when and where he is shipping from. If I manage to find out (within a reasonable timeframe and effort) the location and the timeframe, then I will make sure I'm there to see how he will actually move said slaves. If he does not employ cloaked vessels, fast uncatchable ships or doesn't dock up as soon as hostiles appear and wait until we leave, then I might considering issueing the actual war-dec or suicide ganking his hauler.
Example 5
Somebody let's slip (through intermediaries) that he's aiding slaves to escape from their masters in the Empire, and that he is actually moving slaves from the Empire to another place, that he is doing it himself, leaks the time and place, is convincing that it's not just misinformation, and has a solid reason that he must finish his operation within the timeframe he has given and thus doesn't dock up and wait for me to leave to finish his mission or abort it altogether...
Result: *then* I will be actually issuing that war-dec and/or preparing for suicide ganks.
My point
Unless someone provides me with a lot of very specific triggers, I don't see the point in putting effort into what is likely a ghost chase with many hours invested for zero results.
I know tons of heretics, lawbreakers, illegals, profaners, invaders etc. But unless they provide me with a clear target to aim for, and put themselves willingly at risk, there is simply not a lot I can do to a somewhat smart player.
Incidentally, I've posted on the IGS about a number of operations I was preparing to do, in which I made myself vulnerable in-space and/or provided evidence or pointers to the when and where of my operation. The only people who responded to those operations until now were those who wanted to help me somehow (either known allies, or in a few cases 'neutrals'). I've not yet had opposition by enemies. Maybe because of the reasons mentioned above: too much effort or too little security that they might actually be able to affect the outcome.
Another example:
Some years ago TRIAD posted on the IGS that they were temporarily pulling out of FW to train new recruits and build up war material in high-sec Republic. As soon as I read this, I scouted out their base of operations (I was not in FW at the time), I moved a lot of ships to the an Amarr station nearest to their base and declared war. Then I flew around that area in hopes of encountering a few of them. That was sufficient for me to have provoked a mechical response from me.
2. and 3 (Provoking responses)?
Two options:
1. Shooting them and/or their assets/friends
2. Making public information that damages their reputation.
Really, I haven't got a clue otherwise. Otherwise I would have done so a lot more. I've tried a lot....
Of course, this pertains to provoke 'hostile' responses, its a lot easier to provoke cooperative responses.