An offer of proof—also known as an informal bill of exception—is a procedure available during trial for the presentation of evidence the trial court has excluded. An offer of proof is made outside of the jury’s presence and often after the judge has sustained an objection to the admissibility of the evidence.

A bill of exception—also known as a formal bill of exception—is a procedure that allows a party to complain on appeal about evidence that would not otherwise appear in the trial record (because there was no offer of proof made at trial) by detailing the evidence (testimony, etc.) that would have been offered if the trial court had allowed it.

In North Carolina, an offer of proof is a procedural mechanism used during a trial when the court excludes evidence. This process allows the attorney to create a record of what the evidence would have shown, which is essential for appellate review. The offer of proof is made outside the jury's presence, typically after an objection to the evidence has been sustained by the judge. This ensures that the appellate court can consider whether the trial court's exclusion of the evidence was erroneous and whether it affected the trial's outcome. On the other hand, a formal bill of exception, or bill of exception, is a written statement by the attorney detailing the evidence that would have been presented if the court had not excluded it. This is used when no offer of proof was made at trial, allowing the appellate court to review the decision to exclude the evidence. Both procedures are crucial for preserving issues for appeal when a party believes that the trial court improperly excluded evidence.