Legal Definitions - double proof

Double proof refers to the requirement or presentation of two distinct and independent forms of evidence or methods of establishing a particular fact or claim in a legal proceeding. This approach often serves to strengthen the case, corroborate evidence, or satisfy specific legal standards that demand more than one type of corroboration for a crucial point.

• Example 1: Proving Identity in a Criminal Case

  Imagine a criminal trial where the prosecution needs to prove that the defendant was the person who committed a robbery. To achieve double proof, they might present both eyewitness testimony from a store clerk who positively identified the defendant in a lineup, AND forensic DNA evidence found at the crime scene that matches the defendant's profile. Here, the eyewitness account is one form of proof, and the DNA evidence is a separate, independent form of proof, both pointing to the same fact of identity.

• Example 2: Establishing a Contractual Agreement

  In a civil dispute, a plaintiff claims there was an oral agreement to provide services, which the defendant now denies. To establish double proof of this agreement, the plaintiff might present text messages and emails exchanged between the parties discussing the terms of the service, AND also call a third-party witness who was present during the conversation where the oral agreement was made and can testify to its details. The written communications provide one layer of proof, and the witness testimony provides another, independent layer, both confirming the existence of the agreement.

• Example 3: Demonstrating Ownership of Property

  Consider a situation where someone needs to definitively prove they are the rightful owner of a piece of land, perhaps to resolve a boundary dispute. They could offer double proof by presenting the official deed to the property, recorded with the county, AND also provide a series of property tax receipts and utility bills addressed to them at that specific property over several years. The deed is the primary legal document of ownership, while the consistent payment of taxes and utilities serves as strong corroborating evidence of their long-standing possession and claim to the property.