Adler owes Perreault, a police captain, $500. Adler threatens Perreault that unless Perreault gives him a discharge from the debt, Adler will disclose the fact that Perreault has on several occasions...

Adler owes Perreault, a police captain, $500. Adler threatens Perreault that unless Perreault gives him a discharge from the debt, Adler will disclose the fact that Perreault has on several occasions become highly intoxicated and has been seen in the company of certain disreputable persons. Perreault, induced by fear that such a disclosure would cost him his position or in any event lead to social disgrace, gives Adler a release but subsequently sues to set it aside and recover on his claim. Will Adler be able to enforce the release? Why or why not?