in pari delicto

Etymology
in pari delicto potior est conditio defendentis: "if both (parties) are in the wrong, the position of the defendant is the stronger".

Adjective

 * 1)  In pari delicto describes a case in which involved parties are mutually or equally at fault. In such cases where a party's own conduct is mutually wrongful, that party may not claim damages or satisfaction from the other(s) in a court of law.
 * 2) * "The 'clean hands doctrine', derived from English law, is similar in effect to the Roman law maxim in pari delicto potior est conditio defendentis, which operated as an absolute bar to the grant of relief to the plaintiff. The doctine, also known as the par delictum rule, is concerned with the moral guilt of contracting parties, not their criminal liability.