Striking down both a permission-based system of controls of movement (under which motorists on public streets in the District of Columbia were required to explain the purposes of their intended movements to the satisfaction of police before being permitted to pass police checkpoints, with the burden of justification placed on the would-be travellers), and the use of “security”, generalized crime prevention or deterrence, and general law enforcement as justifications for the use of checkpoints as de facto general warrants to stop, detain, interrogate, and compel responses to questions by travellers on public rights of way, the Court of Appeals for the D.C. Circuit has overturned the denial by the D.C. District Court of a permanent injunction against the Metropolitan Police scheme of so-called Neighborhood Safety Zones.

In Mills v. District of Columbia (No. 08-7127, decided July 10, 2009), the D.C. Circuit Court explicitly addressed, and reaffirmed, both the right to movement on public ways (“It cannot be gainsaid that citizens have a right to drive upon the public streets of the District of Columbia or any other city absent a constitutionally sound reason for limiting their access”) and the unconstitutionality of checkpoint stops, searches, or seizures “whose primary purpose was to detect evidence of ordinary criminal wrongdoing…. Because the primary purpose of the … checkpoint program is ultimately indistinguishable from the general interest in crime control, the checkpoints violate the Fourth Amendment” (quoting City of Indianapolis v. Edmond, 531 U.S. 32).

It’s also notable that the Court ruled as it did despite explicitly noting that the checkpoints at issue applied only to travellers by motor vehicle, and not to pedestrians.  (It’s unclear from the appellate opinion how bicyclists and other travellers by non-motoirized vehicle were treated.)  The undisputed fact that there existed an alternative, unrestricted mode of travel — by foot — was not a factor in the decision.

We’ll leave it as an exercise for the reader, and the TSA, to consider how the logic of this decision — and the Supreme Court precedent in Indianapolis v. Edmond on which it relies — would apply to TSA checkpoints at airports.

Our friends at Checkpoint USA have more details in their Roadblock Revelations blog.