Legal Definitions - law of the trial

The term "law of the trial" refers to a legal principle, rule, or court decision that is applied during a specific trial without either party raising an objection. When a judge makes a ruling or a legal theory is presented, and neither the prosecution nor the defense challenges it, that unchallenged point becomes the accepted and binding framework for how that particular trial proceeds. It essentially sets the ground rules for the case as it unfolds, even if the point might have been debatable under different circumstances.

Here are some examples illustrating the "law of the trial":

• Admissibility of Evidence: Imagine a civil lawsuit where the plaintiff wants to introduce a series of text messages as evidence. The defense attorney could argue these messages are hearsay or irrelevant. However, if the judge rules that the text messages are admissible, and the defense attorney chooses not to object to this ruling, then for the remainder of that trial, those text messages are treated as properly admitted evidence. The judge's decision on their admissibility, unchallenged by either side, becomes the law of the trial regarding those specific communications.

• Scope of Testimony: In a criminal trial, the prosecutor might ask a witness about events that occurred on a specific date. If the defense attorney believes the question goes beyond the scope of the charges or is irrelevant, they would normally object. If, however, the defense attorney allows the witness to answer without objection, and the testimony proceeds based on that line of questioning, then the scope of inquiry established by that unchallenged testimony becomes part of the law of the trial. Both sides are then expected to continue within that accepted framework for that witness's testimony.

• Interpretation of a Contract Clause: Consider a business dispute where the judge issues a preliminary ruling interpreting a specific clause in a complex contract. For example, the judge might state that "delivery" under the contract means the goods must arrive at the buyer's warehouse, not just be shipped from the seller's factory. If both the plaintiff and defendant accept this interpretation and present their arguments and evidence accordingly without objection, then this specific interpretation of the contract clause becomes the law of the trial for that particular case. All subsequent arguments must align with this unchallenged understanding of the contract's meaning.