The Federal Rules of Evidence are a set of rules governing the introduction of evidence in U.S. federal court proceedings. The rules are designed to ensure that evidence is presented in a fair and reliable manner, and to ensure that the evidence is relevant and reliable. The rules are based on common
From Wikipedia
First adopted in 1975, the Federal Rules of Evidence codify the evidence law that applies in United States federal courts. In addition, many states in the United States have either adopted the Federal Rules of Evidence, with or without local variations, or have revised their own evidence rules or codes to at least partially follow the federal rules.