Legal Definitions - all fours

The legal term on all fours is an idiom used to describe two cases, situations, or sets of facts that are so similar in their essential details and legal principles that the outcome or interpretation of one should logically apply to the other. When a previous legal precedent or ruling is "on all fours" with a current matter, it means the material facts, legal issues, and relevant circumstances are virtually identical, making the precedent directly applicable and highly persuasive.

Here are some examples illustrating this concept:

• Imagine a lawyer arguing a new personal injury case where their client slipped and fell on a wet floor in a grocery store. The lawyer researches previous court decisions and discovers a case from the same jurisdiction where a plaintiff successfully sued a different grocery store for a slip and fall under nearly identical circumstances: the floor was wet due to a recent spill, there were no warning signs, and the store employees had a reasonable opportunity to clean it up. The lawyer would argue that this prior case is on all fours with their client's situation, meaning the court should apply the same legal reasoning regarding the store's duty of care and reach a similar conclusion of liability.

• Consider a business dispute between two companies over the terms of a software development contract. Company A claims Company B failed to deliver a specific feature as outlined in the agreement. Company A's legal team finds a previous arbitration ruling involving two other companies that had an identical software development contract with the exact same clause in dispute. In that prior ruling, the arbitrator interpreted the clause in favor of the client, finding the developer liable for non-delivery. Company A's lawyers would assert that the previous arbitration ruling is on all fours with their current dispute, providing a strong argument for their interpretation of the contract and their claim against Company B.

• A homeowner is challenging a local zoning board's decision to deny their application for a minor variance to build a small shed in their backyard. The homeowner's attorney reviews past zoning board decisions and finds a case from the previous year where another homeowner in the same neighborhood, with a property of similar size and layout, was granted an identical variance for the same type of shed. The attorney would present this prior decision, arguing that their client's application is on all fours with the previously approved case, and therefore, the zoning board should grant the variance based on consistency and fairness.