1. The Four Corners of a Contract
2. Times When Outside Evidence Can Be Used
3. Using the Four Corners Rule in Contract Disputes

The four corners rule contract law, also known as the patrol evidence rule, stipulates that if two parties enter into a written agreement, they cannot use oral or implied agreements in court to contradict the terms of the written agreement.

The term "four corners" refers to the four corners of a document. Basically, it implies that the only legal parts of the contract are within the four corners of a page or online document. If there is evidence that exists outside of these four corners, they cannot be used in court if they directly contradict the terms of the written contract.

Types of evidence not valid in court due to the four corners rule include:

  • Conversations about the signing of the contract
  • Written evidence that is not part of the original written contract
  • Comments from the defendant or plaintiff who are in a breach of contract case

The Four Corners of a Contract

Because of the four corners rule, it is vital to include all promise and expectations you have of the other party in the original written contract. If you fail to do so and rely on spoken promises or guarantees made outside of the contract, enforcing them may prove problematic. Any judge looking at your case will look only at the four corners, not whatever verbal agreements you made.

To protect yourself from this type of situation, it is a great idea to speak with a contract dispute attorney. They can look at the contract and make sure it is fair to both parties before you sign it.

Never trust the other party if they say that you shouldn't worry about a particular clause or statement. While you might be in agreement now, if things go south, you will have no legal support for making that party adhere to your wishes.

There are certain times when outside evidence is useful for supporting a contract, but these are mostly limited to instances of fraud or other problems. If you are in trouble and think this might apply to you, contact a contract dispute attorney for assistance. They can determine whether or not you can use outside evidence in a courtroom to defend your case.

Times When Outside Evidence Can Be Used

There are only a few instances when outside evidence is permissible for supporting a written contract. These might include:

  • To correct a mistake in the original contract.
  • To clear up ambiguous language in the contract and help determine the original meaning.
  • To assist the judge or jury understand the contract better.
  • To clarify a transcription error in the original contract.
  • To prove that the original contract is invalid.
  • To prove that consideration was never offered for the two parties.
  • To show that one party committed fraud, interference, unconscionable behavior, or was under duress when creating the contract.
  • To make changes to the original contract if there is a clause that states oral amendments are permissible.
  • To name the parties involved in cases of changing names.

Using the Four Corners Rule in Contract Disputes

If your contract is in dispute in court, the judge will definitely rely on the four corners rule to keep things as simple as possible. They will use your written documents to discover each party's original intention and decide based off that unless you qualify for one of the exceptions listed above.

The court will only use external evidence as much as it needs to clear up the ambiguity or discover the original intent of the contract.

Generally, the procedure for using the four corners rule is as follows:

  1. The judge will read the written contract and decide if extrinsic evidence is necessary.
  2. The court will enforce the contract as written without extrinsic evidence if not required.
  3. If extrinsic evidence is necessary the judge will use the entirety of the contract in addition to the new evidence to make a ruling that is fair.

Overall, a judge will not try to discover hidden meanings or obscure definitions. Instead, they'll use the ordinary and straightforward meaning of words and clauses to determine how certain statements fit into the agreement as a whole.

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