

Probably should have given all of the evidence to the police instead of deleting some of it.
In most western jurisdictions platform operators are not liable for user content, (as long as they cooperate with the authorities) so nothing for you to worry about.
Next time, don’t do anything, no deleting, no blocking, contact the police and ask them what they would like you to do. Maybe they’d even would want to letting them keep posting for a while to gather more data on the offenders, but idk how they deal with selfhosted stuff tbh…
(this is not legal advice)
(Also I totally understand that you don’t want your other users seing that kind of stuff. I know nothing about the matrix moderation tools, so maybe the media is on the server db somewhere … might be relevant to figure that out)
Edit: this does not apply if you live in an authoritarian police state or third world country, like OP apparently does.
w a t ???