Liable for what exactly?

I don’t know of any law in the Florida jurisdiction that would prohibit authoring such documents. But I’m also not an expert in Florida law.

There might be an argument that they’re an accomplice but you’d have to prove that information was written for the purpose of someone else’s crime. And that would be a pretty tough case to argue unless the two individuals had other personal ties. In which case, it’ll be the other ties that likely implicates the author rather than the documents by themselves.

I guess someone could bring a civil case for damages (eg parent of the deceased) but I don’t know if Florida law allows civil cases in criminal investigations. Plus you have the same problem of proving liability (ie did the culprit depend on said documents).

We would need to better understand what you had in mind when you said “liable” to really discuss your point properly.