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 Vermont, an offer of proof is a procedural tool used during a trial when the court excludes evidence. This allows the attorney to create a record of what the evidence would have shown, which is essential for appealing the court's decision to exclude it. The offer of proof is made outside the jury's presence, typically after an objection to the evidence has been sustained. On the other hand, a bill of exceptions is a more formalized document that outlines the evidence that was excluded by the court, allowing for a review on appeal even if no offer of proof was made during the trial. This document is used to ensure that the appellate court is aware of the excluded evidence and the context in which it was offered. Both procedures are designed to preserve the right to appeal by ensuring that the appellate court can review the trial court's decision to exclude evidence.