7000$ is a pitance. Maybe this case is simple, but many will not be. Say they raid a house and confiscate a hard drive. Encrypted or not, that is going to be a huge thing. Arguments will be made about whether anything incriminating was stored on that drive. Just google the cost of a forensic expert witness. Both sides will need one.
Such costs are actually why so many police agencies are backing off of CP investigations. They still prosecute where evidence is clear, such as when someone emails such material openly, but they arent willing to invest the tens and hundreds of thousands of dollars necessary to handle the complex cases involving encrypted communication/storage. 7000$ would be a bare minimum for only the simplest of legal defenses in the simplest of cases.