I've been wondering if Hidden Answers is legitimate. Can I talk about anything on that forum no matter how unlawful it may sound? Really I want to know if it it has connections to Law Enforcement or not.
There is no way to know that. If they were like Facebook and had a signed certificate, you can at least say, "that looks legit" even though they could still be run or have a backdoor for law enforcement. Since there isn't even that, anything you say that can very well be sent directly to law enforcement and you have no way to know and there's no way to find out.
Good rule of thumb, never say anything that can be tied directly to you. The #1 way to be de-anonymized isn't anything technical, it's what you choose to share.