Fourteen years ago, the Rehnquist court interrupted a string of law enforcement victories to rule that when looking for illegal drugs, the police couldn’t simply walk down the aisle of an intercity bus and squeeze the bags and soft-sided luggage on the overhead rack.

The common tactic amounted to an unconstitutional search, Chief Justice William H. Rehnquist wrote for the 7-to-2 majority in Bond v. United States. While passengers certainly expect that their luggage “may be handled,” the chief justice said, that expectation didn’t extend to supposing that anyone “will, as a matter of course, feel the bag in an exploratory manner.”

I remember puzzling over that decision. In one opinion after another, most written by Chief Justice Rehnquist, the Supreme Court had been allowing the police to write their own ticket when it came to detecting drug trafficking. Why draw the line at a duffel bag on a Greyhound bus?

Eventually, it occurred to me: The justices were passengers, too. Not on buses, for sure, but on Amtrak or the shuttle, and the notion that anyone with a badge could start randomly feeling up their carry-ons was deeply distasteful.