What’s good for the geasa…

[computerking]

I am considering a changeling character concept who is half Sidhe, and I was wondering if anyone has figured out a rules-related way to simulate Fae Geasa. I’ve read the Oathbreaking sidebar in regards to the topic, but it, much like the fae themselves, gives a lot of information without giving a lot of helpful information. I wanted to see if anyone else has run into the same stumbling block and overcame it before I take a hard try at it myself.
 
To make it more specific, The concept is a Half-Sidhe Lawyer. He works as a defense attorney, and in initial conference with his clients, he negotiates a deal: If the client is 100% honest in answering his questions, he will represent them pro bono, and make sure to get them the best sentence possible, depending on the evidence. But if the client lies to him, even just once, They owe him a year and a day of favors. He gets them to swear 3 times to uphold the deal, then starts asking questions, starting with (of course) “did you do it?”
 
If the client lives up to the oath, Everything’s jake, and the Lawyer upholds his end of the bargain. But if the client breaks the oath, The lawyer would know, and be able to compel the client for a year and a day. Has anyone come up with a good way to model this “power”?

[devonapple]

The super-easy way is simply to Invoke your High Concept with a Fate Point. Or a secondary Aspect like "Fairy Bargainer" or "The Geas Guarantee."

If that's not enough, then you may need to drill down to what you actually want to accomplish in the game, and reason from there.

Detect Lies? buy Supernatural Sense: Deceit.

Squeeze your oathbreaking clients for favors: a stunt that gives a bonus to setting up Maneuver Aspects using Resources or Contacts (or any one skill you justify) if you can justify it as coming from one of your geas-bearing clients.

Make them yours? Take Rituals: Fairy Bargains. Set up a Ritual. when a client Concedes, no consequences. If they lie (resist), you have to "take out" your client, and change one of their Aspects to "In Debt to a Half-Sidhe Lawyer."

[Masurao]

Well, devonapple has given you most of the ideas of how to run with this and I think you've hit a really fun character concept there, though perhaps it would suit a NPC better, depending on the type of game your playing. Meaning, how often would this ability affect play in general?

On the other hand, I would use a different way of quantifying the favours owned to the character. A year and a day is a pretty standard time-frame when it comes to faerie bargains, but how do you express this in favours? Is the unlucky patsy your bitch for that exact time, or could you call upon his help from time to time and each time he answers, he pays off at least a day of debt? So, if he does a week of a legwork for you by sifting through papers, he trades in a week of debt, but if he has to risk his life during a single day, it is still worth a single day?

[gaelvin]

Another way to go would be to run the initial client interview as a Mental Conflict; do enough Mental Stress to force the client to take a Severe or Extreme Consequence: Geasa. Then it could be Compelled for as long as it remained in place.

The real interesting thing would be to model the Conflict in such a way that the client would cause Stress on himself whenever he lied.