TMZ has obtained a letter Warner Bros. sent to Charlie Sheen's lawyer, stating Charlie was being terminated because he committed a felony involving "moral turpitude."



In the 11-page letter, obtained from sources connected to Charlie, Warner Bros. states, "Your client has been engaged in dangerously self-destructive conduct and appears to be very ill."

The letter then goes on to describe Charlie's hijinks, including trashing the Plaza Hotel in NYC, coke binges, on-set failures because of drug fatigue, and diatribes against "Two and a Half Men" creator Chuck Lorre.

The letter also notes that Charlie derailed production when he went into rehab, and then he fired his sobriety coach.  In fact, Warner Bros. claims it was so concerned about Charlie's well-being, "Warner Bros. had an airplane waiting" to take him to a treatment facility ... but Charlie would have none of it.

As for why Charlie got fired, the letter says there is a clause in his contract saying they can fire a performer who commits "a felony offense involving moral turpitude."

The letter says, "There is ample evidence supporting Warner Bros. reasonable good faith opinion that Mr. Sheen has committed felony offenses involving moral turpitude (including but not limited to furnishing of cocaine to others as part of the self-destructive lifestyle he has described publicly) that have 'interfere[d] with his ability to fully and completely render all material services required' under the agreement."

In short, that's why Charlie was fired.

Charlie's lawyer, Marty Singer, has demanded Warner Bros. pay Charlie for the eight canceled episodes -- or else.