extortion is a crime. http://apps.leg.wa.gov/RCW/default.aspx?cite=9A.56.120. If you have been a victim of a crime, you should call the police.
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But on the other hand, statements made to a judge are privledged. And frankly, any one can tell a judge any darned thing they want. The Judge has heard it before, I promise you. And the threat to promise to keep quiet in exchange for a reduced support obligation - unless John could PROVE that an exotic dancer was somehow a less capable parent (on the basis of her career) . . . and well. Good luck with THAT. WA courts believe that both parents should be out working at least 40 hours a week, and the child should be in care. I kid you not.
The only thing John would be demonstrating to the Court is that he has terrible judgment. I wouldn't have to do anything, I'd stand back and let the Court do its job.
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