Final answer:
A contract formed under duress or undue influence can be voided because it lacks the parties' free consent. Duress involves coercion, while undue influence involves abusing a power position. Legal precedents underscore the necessity of informed, voluntary consent in binding agreements.
Step-by-step explanation:
When a contract results from duress or undue influence, it is considered to be executed under circumstances that compromise the voluntary nature of the parties' agreement and can be declared void or voidable by a court.
The impact of duress involves coercion or a threat of harm that forces an individual to enter into a contract, while undue influence occurs when one party takes advantage of their power over another to unduly influence them into entering a contract.
In the legal cases mentioned, such as Strickland v. Washington and Padilla v. Kentucky, we see the emphasis on the importance of informed consent and the consequences when proper protocol is not followed, paralleling the criticality of informed and voluntary agreement in contracts.