Intro to the Federal Rules of Evidence - 42

4. Prior Inconsistent Statement (FRE 613(b))
a. Requirements
i) Foundation
Before the statement may be introduced, the witness must be given a chance to deny having made it or to explain away the inconsistency.

But extrinsic evidence need not be shown to the witness before the inconsistency is revealed (FRE 613(a)).

1) Court’s discretion to dispense with the requirement of the chance to deny or explain :
“[I]f the interests of justice otherwise require.”

ii) No extrinsic evidence on collateral matters

iii) Parties not covered
The requirements of foundation and no extrinsic evidence on collateral matters apply only where the witness is not a party. If the witness is a party, his prior inconsistence statement is substantively admissible as an admission, since admission do not fall within the hearsay rule. See the last sentence of FRE 613 (b).
b. Method
i) on X-X
ii) Extrinsic evidence, subject to the collateral evidence rule (FRE 403).
c. 613(b) v. 801(d)(1)(A)
Prior inconsistent statements made under oath at a trial, hearing, or other proceedings are admissible for both their truth (as substantive evidence) and impeachment. But those not made under oath can be admissible only for impeachment.

Whenever a witness impeached with a prior inconsistent statement not made under oath, the judge must, on request of a party, instructs the jury to consider the statement only for the limited purpose of assessing the witness’s credibility and for no other purpose.