I wouldn't think for a moment of passing judgment on the propriety of the Cambridge police arresting a prominent professor of African-American history for breaking into his own home (roll that sentence off the tongue a few times). But I will offer what I take to be a an instructive anecdote.
Here at Palookaville U, we enjoy the presence and services of one of world's foremost authorities on the butterfly. He's a treasure and a lovely guy to boot. But he looks like a street person--scraggly beard, ducktaped Levis (okay, I made up the ducktape, but you get the idea). In short, he looks like a hobo. And being a butterfly expert he spends a lot of his time hanging out under bridges.
My wise friend Ignoto says: it is the job of a Palookaville cop to know the difference between Dr. Butterfly and a hobo. Even though it is not obvious, it his job.
Jump cut to Cambridge. Let's stipulate from the outset that when a cop sees two guys with backpacks trying to force the front door, it is not unreasonable to inquire. Let's stipulate that if this had been a real burglar and the cop had given him a bye, why then he would have been in trouble for that, too. I would also like to believe (though I am sure this is more contentious) that it is not actionable to address a cop as "Yo' Mama."
But n0ne of this is the point. The point is that if you are a cop, you do not want things like this to happen, period. You don't want to get into a mess where your story is going world wide in every major news outlet. You want things to be orderly, peaceful, and, most of all, quiet. Move along, folks, nothin' to see here.
As a minimum, I would think this means knowing something about your neighborhood. The story says that the professor lived "a few blocks from Harvard Square." My guess is that this is a fairly upscale neighborhood, full of high-prestige famous-all-over-town celebrities with (I suspect) a vast sense of entitlement (not, we are not talkin' race here; we're talkin' Harvard professor). A good cop is going to know who is who, or, more precisely, who expects to be recognized, and who will ring the phone off the wall in the chief's office in the morning if he is not. A good cop at work in his own neighborhood knows the difference between a Harvard professor and a housebreaker.
And again quite aside from the narrow rightness of the matter--I'll bet that's what his shift commander was telling him after it all blew up last night.
Aferthought: One more anecdote which probably doesn't prove anything. I used to have a '65 Mustang --crappy car, dumb mistake. But one night, I left work at the University to make the 90-mile (sic) drive home. I quickly determined that was way too foggy to drive; I turned around with the purpose of dumping my car in a campus parking lot, and then walking over to a motel. I saw the blue light behind me.
I got out of the car and walked back to the cruiser. "I don't know what you stopped me for," I said, "but I probably did it..." and then told him what I just told you now.
The cop was black, a compact little man with sergeant's stripes. Once he saw I was an old white guy, he lost all interest in me. "Okay, professor, have a nice night..."
Review the bidding: an old Mustang creeping around campus at eight miles an hour in the dark. Not a bad call, was it?
Update: Hoo boy, that didn't take long.