If the private key was hashed, and they only had the hash, then they could not crack it. Hashing is not the same as encryption.

Hashing is for ensuring data integrity and encryption is for protection of data and information I know it but I meant hashing bitcoin private key with some hashing algorithm in order to conceal it.

Second reply: I saw that you work in applied cryptography and blockchain technology @ Cryptography Services (NCC Group) so you might be familiar with somewhat Grey Hat russian forum InsidePro; back in the day I saw people there requesting Bitcoin private key recovery for their lost private keys or if they encrypted and/or hashed wallet private keys and couldn't recover plaintext anymore and I can say that amateur crackers could recover private keys pretty efficiently and I can only wonder what professional law enforcement agency can do.

If FBI could crack smartphone encryption/protection from multi trillion dollar company I'm speaking about Apple and that terrorist's Iphone then they do pretty much anything.

> amateur crackers could recover private keys pretty efficiently

That's only if the key was derived from a weak password, which allows it to be brute-forced with standard password scanning techniques. If you're even slightly concerned with security you let a computer generate a fully random key using the proper amount of entropy—preferable on an air-gapped system or an HSM (hardware wallet). No one is going to be "recovering" private keys which were generated and handled securely without a very large budget and physical access to the storage medium.

Can they travel faster than light?

I never heard of any criminal that's fast as light so they do not need to be faster than light in order to catch him.

It could've been*