Yes, which is why there aren't a lot of NSFW communities right now.

You can be pretty safe if you ban NSFW and have a good hand in moderation, and most of the time if the feds did come knocking it would probably be just to ask for the user who did post it and to give all information on them.

Users love to complain that there is no NSFW in most places on lemmy but then refuse to accept any of the responsibility of hosting it.

If you are US based, I think there is something like registering for DMCA take-down requests, so that they will contact you first for removal but IANAL.

But it is pretty much FUD that the Feds will come to your door on the first minor issue. If you react quickly to any complaints they will probably not bother.

Assuming USA - platform immunity (CDA 230) protects you from most liability for content originating elsewhere. There are specific requirements to maintain your immunity if you receive a DMCA takedown notice, or have actual knowledge that child pornography has been uploaded to your service.

Related, What about a personal instance only I use? I can choose what communities I want but I can't control what is posted on those communities. Someone could post something illegal to a beehaw community (and have) and the mods remove it, but does the deletion of images and posts federate? In know matrix keeps copies of every deleted file in a room on all homeservers, what about lemmy?

Maybe. First you should check out https://en.m.wikipedia.org/wiki/Section_230 which explains websites generally aren't responsible for users posting their own content. However, that's not a clear protection from anything. If you end up with blatantly illegal material, you will be investigated and forced to turn over data, surrender equipment, etc. They would have to prove that you were aware and complicit, but it's generally not worth the trouble unless you're making money from it. That being said if you got a lawyer that is familiar with section 230 to look over a disclaimer and your intentions, you're probably fairly protected. Also, the smaller you are, generally you're much less likely of being targeted should something happen.

Disclaimer; I'm not a source of defensive legal advice.

I'm sure you're liable if you don't moderate. I'm no lawyer, but it's certainly possible to host things without ending up in prison. google, reddit, etc and lots of other people and companies do it. and they had that happen.

You haven't discussed either your jurisdiction or what you're worried about hosting. But in general, if you're hosting a service for others... yes... they can create legal liability for you. And with lemmy specifically it's not just what your users create, but what they subscribe to since subscribed content gets replicated to your instance and then served to the unauthenticated public internet.

People/companies obviously do host things safely, but you need to learn how things work in your local jurisdiction. Like on the US, you need to register as a copyright agent to get DMCA protection, failure to do so could expose you to personal liability for the copyright infringement others sub/create. For CSAM (aka child porn), you may be required not just to remove but to report it as well.

There are definitely people hosting Lemmy instances today who have no understanding of the legal implications of doing so are are not taking the necessary precautions to protect themselves. The vlemmy instance just disappeared without warning or communication, and while no one knows why, it's not out of the question that they got spooked by a child-porn situation or got their server raided by police (this is speculation, but it's possible). Other instances will disappear at some point when admin responsibilities get real.

Your most important responsibility as an admin is understanding the legal/compliance environment you operate in and doing whatever is required of you to host safely. It's not a trivial task, but people do it successfully.

You probably would be, but that depends on the law where the server is hosted. This isn’t a good place for legal advice like that.

What kind of server do you want to host?

Dude. 4chan exists and continues to exist. This fact alone should allay your fears.