term:

Overreaching

overreaching n

1 : conduct that exceeds established limits (as of authority or due process) [claimed that by the prosecution barred a retrial because of double jeopardy]
2 : the gaining of an unconscionable advantage over another esp. by unfair or deceptive means [if the contract was void for traditional reasons such as fraud or "Lugassy v. Independent Fire Ins. Co., 636 So. 2d 1332 (1994)"]

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.