In Crittenden v. McCoud (1951) 106 Cal.App.2d 42, the plaintiff lawyer claimed title through a deed that he knew to have been forged, indeed as to which forgery he was an active participant. More specifically, he impersonated his client (who was then incarcerated and had told his wife to get rid of real property) in obtaining notarization of a deed of trust transferring full title to real property to the client's wife. Later on, the wife sold the property to the defendant. The client, then out of prison, was with his wife when she cashed defendant's check for payment of the Property and immediately purchased a new property. At no time did the client disclose to the defendant that defendant's deed was forged, although the client knew his signature had been forged at the time he and his wife cashed the defendant's check and had purchased a new property. Subsequently, the client conveyed a half interest in the property to his lawyer, who sought to quiet title against the defendant. Under these facts, the appellate court found that the plaintiff attorney was estopped from denying the validity of the forged deed. (Crittenden, supra, 106 Cal.App.2d at pp. 48-50.)