Evidence

Prior Inconsistent Statement

It is possible for one to have previously remembered something, but not know it now without lying. They could have forgotten. Forgetfulness is not an inconsistent statement unless it is faked.

Evidence of a prior inconsistent statement can be read in court. FRE 613.

A prior inconsistent statement can be admitted even if it is not direct impeachment. (Barrett v. United States allowed one to testify he heard the witness testify something else earlier.)