A planned stop, not a suspicion stop
A sobriety checkpoint stops drivers without any individual reason to suspect them, which the US Supreme Court has allowed under the federal Constitution when the checkpoint runs under neutral rules. Some states bar or restrict checkpoints under their own law, but New York permits them. Agencies often schedule Halloween checkpoints because the night brings heavy traffic and many parties, and they sometimes announce them ahead of time. The legal questions usually turn on whether the checkpoint followed a plan set by supervisors, rather than leaving officers free to choose whom to stop. A checkpoint that was run loosely can raise issues an ordinary traffic stop would not.
At the window and after
At the first contact, officers usually ask a few questions while looking and listening for signs of drinking. You are generally expected to hand over a license, registration, and proof of insurance, but you do not have to describe where you were or how much you drank. Turning around before reaching a checkpoint is not automatically illegal, yet a traffic violation committed while doing so can give officers a separate reason to pull you over. Drivers sent to a secondary area may be asked to do roadside exercises or blow into a screening device, and the evidential chemical test usually comes after an arrest, under implied consent rules. Staying calm and keeping answers short tends to serve people well.
What we request about the checkpoint
Because the legality of a checkpoint depends on how it was actually run, the documents behind it matter. Supervisors' written guidance, the reasons the site was chosen, and any tally of cars waved through or held can all be requested. Patrol car and body camera footage may show how drivers were picked out and how long each stop lasted. We ask for that material early, since agencies keep recordings for limited periods. In a first conversation we go through what happened at the window, what you said, and why you were sent to the secondary area, because those details decide which questions are worth pressing.
