It does not seem that anyone in the media has actually talked to an attorney that has researched the law in this area. I researched the statute under which Prof. Gates was arrested. The courts have interpreted it very narrowly to permit arrest based on disorderly conduct only where the actions went beyond merely speech (such as a threat of physical violence or other physical threat) or the speech amounts to "fight words" (which basically means that he words themselves are so offensive that we would not expect a reasonable person to be able to control himself or herself from attacking the person--or the words otherwise are an incitement to violence). Any other speech is constitutionally protected by the First Amendment, and an arrest for that speech is a civil rights violation under federal law.
I have read the police report and even if it is accepted as true (which I do not necessarily accept), there are no allegations of any threat of violence or anything that reasonably could amount to "fighting words" as that term is understood. The police report, read with knowledge of the relevant caselaw, essentially is a concession by Sgt. Crowley that he violated the civil rights of Prof. Gates, and Prof. Gates should win a motion for summary judgment if he sues Sgt. Crowley. The police do not seem to understand the law (not that I am that suprised about that fact).
If anyone wants to read the relevant caselaw, the leading case is Levine v. Clement, 333 F.Supp.2d 1 (D. Mass. 2004). This is a U.S. District Court case for the District of Massachussets decided in 2004. A man was arrested under the same statute as Prof. Gates. The man had been yelling at a parade regarding the Canadian flag (reportedly including the F-word to describe Canada and its flag). A police officer asked him to change the manner in which he was expressing himself. He yelled at the police officer refusing to change his manner, and reportedly challenged the officer to arrest the man. The officer arrested him for disorderly conduct (as noted above, under the identical statute as was cited in the police report for Prof. Gates). The court held that disorderly conduct can only be applied against speech that is not constitutionally protected, and that "neither a provocative nor a foul mouth" can be deemed disorderly conduct and that there must be conduct that "disturbs through acts other than speech." The court ruled on summary judgment that the officer violated the man's civil rights and was not entitled to qualified immunity because no reasonable officer could have believed that the man's behavior was not constitutionally protected.
In my view, Prof. Gates has an even stronger case because he was on his own property, not at a public event. It is clear that the police report does not suggest any behvior by Prof. Gates other than behavior that is constitutionally protected. Prof. Gates made no threats and used no words that are inherently injurious or an incitement to violence. If I lived in the Boston area, I would volunteer to help on his civil rights law suit.
Another interesting and relevant case is Commonwealth v. A Juvenile, 368 N.E.2d 617 (Sup. J. Ct. Mass. 1975), in which the Supreme Judicial Court of Massachussets indicated that the disorderly conduct statute must be interpreted narrowly as to prohibit only speech that is not constitutionally protected. In that case a juvenile was yelling and swearing at a police officer and was arrested and convicted. The conviction was overturned by this court because even though the behavior seemed to meet the requirements of the statute, application to that behavior would be unconstitutional. Again, the actions of Prof. Gates were less likely to be speech that is not constitutionally protected than the behavior at issue in this case.
I hope that this understanding of the law becomes more widely understood. If that happens, hopefully people will understand that a police officer has no right to arrest someone for constitutionally protected behavior--even if that behavior is in the form of rude and offensive speech.