Alteration

Alteration refers to any unauthorized change made to a document or instrument, which can render it void or unenforceable. This principle underscores the necessity for consent and adherence to formalities in contractual agreements and legal instruments.

The concept of alteration has roots in common law, stemming from the need to ensure the authenticity and integrity of contractual documents. Historically, unauthorized changes were seen as threats to the reliability of legal instruments.

In modern law, alteration is a critical element in the assessment of contract validity and enforceability, especially in disputes over contractual terms. Courts may consider whether the alteration was made without consent and if it materially affected the parties' rights or obligations.

• A party unintentionally adds a clause to a contract after both parties have signed, changing the agreement's terms.
• An individual alters a check's amount after it has been issued, which may lead to fraud allegations and nullify the check.

• Sherwood v. Walker, 33 Mich. 543 (1876) - addressed unauthorized alterations in the context of property contracts.