There is now a subforum which has been created specifically to host debates between individuals or opposing parties:
The only steadfast rule for this subforum is that when a debate thread is agreed upon, only those who are acknowledged as debate participants are allowed to post in the thread. If, for example, two people wish to have it out in a debate thread, only those two will be able to post there.
For other members, associated comment threads can be created. There may be any number of comment threads associated with a single debate. These should be located in the new subforum, ideally, but this is not required.
All other rules are established by mutual agreement between the debate participants. There may or may not be moderation in the debate, depending on the participants' desires. Comment threads will be moderated but, as usual, as little as possible.
IMPORTANT NOTE: the forum software doesn't support per-thread access restrictions, therefore a subforum under the Debate Area will be created for the debate participants, identified by their user names. Only they will have posting access. One or more distinct debate threads between them can be started within.