I've read similar stories about lost police documents. A public blockchain could be useful to prevent that.
The police exist to protect the property and station of those in power. It's why New York City was able to function without a police department until the 1840s while the New York Fire Department can trace its history back to the 1640s.
Pretty suggestive that in this case, the police were able to demonstrate a binding order from someone who was not an 'officer'.