Meh, police get the address wrong sometimes. I could totally see them either not understanding of not believing a 'no logs' policy. So they get a warrant for '

Meh, police get the address wrong sometimes. I could totally see them either not understanding of not believing a 'no logs' policy. So they get a warrant for 'servers with client connection logs' and when they arrive they discover that there are no servers - nothing with a HD and certainly no storage systems, and then they contact their boss and are more willing to re-examine and maybe decide to trust that the company was being honest. Mullvad don't say they weren't searched, just that nothing was taken. They informed the police that what they wanted didn't exist and demonstrated it to the police/prosecutor's satisfaction. Cops have access to technical consultants if they need expertise to verify this. Good code and wiring probably helped - if there's a rat's nest of cables running into the ceiling it's hard to trust, but if there's a really clean patch panel and short direct runs between equipment it's easier to demonstrate that what you see matches the device map and how it's configured.