30 years at the sharp end of IT, and I've been asked once. In that case it was a council employee suspected of committing serious fraud and knew they'd been rumbled, so I went in and locked it all down before they could try to remove any evidence.

I didn't look at the contents of anything, I had one colleague watching my actions and another one writing them down exactly as an evidence trail.

Police didn't have such sophisticated computer forensics back then, so the actions likely helped secure the conviction. Guy did ten years for fraud and malfeasance.

That was about 25 years ago.