What happens if key evidence gets destroyed, altered, or lost after an injury? That is spoliation: the failure to preserve evidence that is relevant to a claim, defense, or anticipated lawsuit. It can involve physical items, documents, photographs, video, lab samples, maintenance logs, or electronic data. Spoliation may be intentional or negligent. The core issue is not only that evidence is missing, but that a party had reason to preserve it because litigation was pending or reasonably foreseeable.

In practice, spoliation can change the outcome of a case. If a hospital discards records, a manufacturer overwrites equipment data, or an employer disposes of a damaged tool before inspection, the court may conclude that the missing evidence would have been unfavorable to that side. That can lead to an adverse inference, limits on testimony, exclusion of other proof, monetary sanctions, or other discovery penalties.

In Massachusetts, the leading case is Keene v. Brigham and Women's Hospital, Inc., 439 Mass. 223 (2003). The Supreme Judicial Court confirmed that when evidence is lost or destroyed by a party who knew or should have known the evidence was relevant to likely litigation, the trial judge may impose sanctions tailored to the prejudice caused. In an injury claim, that can affect proof of causation, negligence, and damages, especially where the missing item is the only direct evidence of how the incident occurred.