This may seem like a plot point straight out of a crime thriller, but this really happened in Washington D.C. An evidence vault at a police department was struck by an explosion recently, damaged evidence packets. About 150 of the packets suffered "significant" damage or were destroyed. It is unclear exactly what "significant" means in this context, but since it is paired up with packets that were "destroyed", it sure sounds like the evidence is no longer admissible.
The police are looking into the incident and have not released any details about what caused the explosion. For now, we are also left wondering how many packets suffered damage, but were not deemed damaged enough to be "significantly" damaged.
This is one of the fascinating aspects of this story. What does it mean for the evidence to be "significantly" damaged? What does it mean for packets of evidence to be damaged, but not "significantly"? What testing will be done to determine if this evidence can be presented at trial without allegations of the evidence being tainted? Will cases be dropped as a result of this explosion?
The answer to the latter question is "probably yes," especially for the cases that were linked to the 150 "significantly" damaged packets.
Evidence makes or breaks a case. If the evidence in any given case is destroyed or tampered with -- may it be due to a freak incident like an explosion, or due to negligence on the part of the police or technicians at a lab -- then the accused and their criminal defense attorney must press their advantage.
Source: Washington Post, "Explosion in vault had minimal effect on drug evidence, D.C. police say," Peter Hermann, Feb. 2, 2017