Since I am not an attorney I will give you my best guess (since stating anything otherwise would potentially open me to a liability for dispensing legal advise without being licensed to do so).
Generally speaking, if someone KNOWS FACTUALLY that criminal activity is ocurring yet, does nothing to report it or stop it then, that person is usually charged with abetting the crime. Depending on the crime the charge may be minor of it could be a felony.
For example, if you rob a bank and I drive the getaway car and you shoot and kill someone, I am guilty of murder just as you are since I knew there was going to be a crime committed (the murder charge would be in the second degree unless, you PLANNED beforehand to kill the teller, for example).
The same principle applies here. If someone KNEW another poster was posting false information with the INTENT to defraud, they would have a legal obligation to report it. Especially, if that someone is the operator of a message board. That is why I believe the day will come when some board operators WILL face criminal charges as they have had the fraudsters reported to them, and it can be documented as such, yet, they refuse to stop the purpetrator. They are as guilty as the fraudster.
I hope this helps, even if only a little. Just stay tuned as the day will come, IMO, that you will see message board operators sued for this very thing.
From the magical fingers of............. CoolBreeze!
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