The mystery witness in the Nicollette Sheridan trial has come forward and testified about an email he accidentally received calling for an alleged coverup of Sheridan’s firing from Desperate Housewives.

Michael Reinhart, who is a construction coordinator for the show, said he called Sheridan’s attorney, Mark Baute,  because his conscience was bothering him.

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“It started gnawing at me it was really bothering me at the end,” he told the jury. “I started losing sleep on it. Given the amount of time left [in the trial against Marc Cherry] that’s why I acted the way I acted.”

The construction worker also acknowledged testifying against his boss was “professional suicide.”

Reinhart says he deleted the email after he got it, but he couldn’t forget it. Cherry’s attorney’s have subpoenaed his computer to  retrieve the email, but Judge Elizabeth Allen White has given them until the end of the day Tuesday to find it, because she wants the case to go to the jury on Wednesday.

Our RumorFix reporter in the courtroom says the jury was shocked by the revelation.

Sheridan is suing Cherry and Touchstone Television Productions for $4 million in a battery and wrongful termination lawsuit.