When investigating crimes involving VPN misuse, authorities typically:

1. Identify Digital Footprints: Analyze logs and metadata to trace activities back to potential VPN usage.
2. Collaborate with VPN Providers: Request user data from VPN companies, especially those complying with local data retention laws.
3. International Cooperation: Engage with global law enforcement agencies if VPN servers are located overseas.
4. Technical Analysis: Utilize advanced cyber forensic tools to de-anonymize users.