This question was inspired by Did Michael Jackson sexually abuse children? as some moderators discussed the question with the OP in comments and suggested that perhaps Skeptics can not replace the trial process and there should be some meta discussion before attempting to answer the question.
However, the accusations in the Jackson case are no worse than those in (Is there systemic sexual abuse of children by Catholic priests?), which is answered. In fact, as Jackson is dead the potential for damage would seem to be less than the damage for an existing organization that holds itself out as religious and charitable and takes in donations.
Factual truth and legal status can diverge -- a murderer or rapist could be found not guilty at trial -- when in fact they committed the crime -- because the prosecution did not meet the burden of proof at criminal trial (which is "beyond a reasonable doubt" in the USA), or perhaps be immune from prosecution and never face trial (e.g. Did the US government have prior knowledge of 9/11?)
Also related: Did Lee Harvey Oswald kill John F. Kennedy?
Unposted, but forseeable:
- Did American football player/celebrity OJ Simpson kill his ex-wife Nicole Simpson? (He was found not guilty at criminal trial but found liable for her death at civil trial because in part of the lower burden of proof at civil trial "preponderance of the evidence", i.e. more likely than not. Later he wrote a book titled "If I did it")
- Did President Bush commit war crimes by lying to the American people about Iraqi WMDs to gather support for an unjust war and by permitting torture?
- Did an American TV Preacher have his first sexual encounter with his own mother in an outhouse? This was a hoax, but clarifying a hoax is generally on topic and this example in particular illustrates the futility of prosecuting an opponent for slander in the US if you are a public figure Falwell v Flynt Trial Archive at UMKC
It may be that no blanket policy is needed.
But I can imagine Stack Exchange Inc being concerned about the possibility for defamation charges. In the USA, such discussion of public figures tends to be common. However, as @Oddthinking and @Flimzy point out, it seems that discussion here would have to be limited to what can be documented and cited, and a number of talented professionals in law and law enforcement will have looked at the evidence. It may boil down to second guessing a jury without sitting in a trial for days, or weeks as the jury did.
Wikipedia has a policy for Category:Living People to avoid defamation and inaccuracy.
On the other hand, the fact that some of these have been asked and answered suggests that at least some questions in the area of infamous crimes/allegations are on topic.
Should there be some kind of policy to guide topicality or should these handled case-by-case?