Police officers in New York City and throughout New York State typically rely on the administration of a breath screening test to help them establish probable cause to make a DWI arrest. The most commonly used breath screening device is the Alco-Sensor, manufactured by Intoximeters, Inc. The Alco-Sensor is a hand-held device, designed to operate as a screening device for the presence of alcohol. Most courts in New York State do not consider PBT's administered roadside to be accurate enough to determine a specific blood alcohol concentration.
Vehicle and Traffic Law § 1194(1)(b) provides that a motorist is required to submit to a breath screening test if he has been involved in an accident or has committed a traffic violation. This law, by its operation, is problematic. Since a breath test is clearly a “search” under the 4th Amendment to the U.S. Constitution, the officer would need probable cause of the commission of a crime to require a breath test. The law, as it is written, requires a motorist to submit to a breath test if stopped for speeding, or running a red light, or any other non-criminal traffic violation. This is almost certainly unconstitutional, and several courts in New York as well as the leading DWI treatise in New York have reached this conclusion.
Despite the constitutional concerns, as a practical matter, individuals stopped on suspicion of DWI, particularly in New York City, are routinely offered breath tests at the side of the road. While a PBT result, or refusal to submit to a PBT, should not be sufficient to establish probable cause, police officers will almost always offer a few more incriminating facts, so that the PBT result along with observations such as blood shot eyes, slurred speech, and/or the odor of an alcoholic beverage will usually suffice to establish probable cause.
The results of a PBT test should never be admitted in evidence at trial. Several courts in New York City have recently allowed PBT results into evidence, but these decisions are against the weight of legal authority in New York. The fact of a refusal to submit to a PBT should also never be allowed into evidence. Due to the recent changes in New York State's discovery law, details regarding the maintenance and calibration of the PBT device should be made available in any DWI prosecution.