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Holiday season means DUI checkpoints increase across the State of California. DUI checkpoints are legal and police may use them in an effort to protect public safety, if they follow certain guidelines in setting up and operating the checkpoint.

Vehicle Checkpoints and the Ingersoll Test

  The primary purpose of a sobriety checkpoint is to “prevent and deter conduct injurious to persons and property,” rather than the detection of criminal activity. Ingersoll v. Palmer (1987) 43 Cal.3d 1321, 1331. A checkpoint operated for the primary purpose of detecting criminal wrongdoing, as opposed to enhancing public safety or similar purpose, is unlawful as violative of the Fourth Amendment’s proscription against unreasonable searches and seizures. City of Indianapolis v. Edmond (2000) 531 US 32, 41-42. For this reason, the California Supreme Court has concluded that the validity of sobriety checkpoints “is to be determined not by the standard pertinent to traditional criminal investigative stops, but rather by the standard applicable to investigative detentions and inspections conducted as part of a regulatory scheme in furtherance of an administrative purpose,” to ensure that, “the primary purpose of a sobriety checkpoint is not to detect evidence of crime or arrest drunk drivers”, but to, “promote public safety by deterring intoxicated persons from driving on the public streets and highways. Ingersoll at 1328.

The Ingersoll Factors and their Relation to the Fourth Amendment

             The California Supreme Court articulated eight “Ingersoll factors” which serve to be used in a Fourth Amendment “balancing test: weighing the gravity of the governmental interest or public concern served and the degree to which the program advances that concern against the intrusiveness of the interference with individual liberty.” Id. at 1338. The “eight factors identified in Ingersoll provide `functional guidelines’ to assess the intrusiveness of a checkpoint.'”  Roelfsema v. Department of Motor Vehicles (1995) 41 Cal.App.4th 871, 877. Those eight factors are as follows:

(1) Whether the decision to establish the checkpoint, the selection of the site,   and the procedures for operation are established by supervisory law enforcement personnel;

(2) Whether motorists are stopped according to a neutral formula;

(3) Whether adequate safety precautions are taken, such as proper lighting, warning signs, and signals, and whether clearly identifiable official vehicles and personnel are used;

(4) Whether the location of the checkpoint was determined by a policymaking official, and was reasonable;

(5) Whether the time the checkpoint was conducted and its duration reflect “good judgment” on the part of law enforcement officials;

(6) Whether the checkpoint exhibits sufficient indicia of its official nature (to reassure motorists of the authorized nature of the stop;

(7) Whether the average length and nature of detention is minimized, and;

(8) Whether the checkpoint is preceded by publicity.

People v. Alvarado (2011) 193 Cal.App.4th Supp. 13, 16-17, citing Ingersoll, supra, at 1341-1346.

The Court concluded that “while the intrusiveness of a sobriety checkpoint stop is not trivial, the enumerated safeguards operate to minimize the intrusiveness to the extent possible. The fright or annoyance to motorists condemned in connection with roving stops is absent when the checkpoint is operated according to the guidelines followed here.” Ingersoll, supra, at 1347.

            In its decision, the Ingersoll court described the importance of each factor in minimizing intrusiveness into individual liberty and ensuring that the checkpoint is serving its administrative purpose, rather than being used primarily to detect criminal wrongdoing. See Ingersoll, supra, at 1341-1347.

            The first factor, concerning the development of the checkpoint by supervisory personnel, rather than field officers, is “important to reduce the potential for arbitrary and capricious enforcement” of the sobriety checkpoints. Id. at 1341-1342. The second factor, whether a neutral formula was employed to limit field officer discretion as to which vehicles are stopped, is also necessary to minimize the prospect of arbitrary enforcement. Id. at 1342. The third factor, the presence of adequate safety precautions, is necessary to ensure that the administrative purpose of the checkpoint of safer road, “necessary to minimize the risk of danger to motorists and police,” posed by checkpoints, such as ensuring that there are “no safety problems with respect to traffic backups.” Id. at 1342-1343.

            The fifth factor, relating to the reasonableness of the time and duration of each stop in connection to the checkpoint, is a necessary consideration to ensure that motorists are not unduly surprised by the roadblock, but still operated at a time in which the checkpoint would be most effective and in a safe manner, both related to minimizing intrusiveness of the roadblock while ensuring effectiveness of roadblock’s purpose. Id. at 1345. The sixth consideration, relating to the official nature of the roadblock, is necessary to ensure that the motorists understand that the roadblock is authorized and giving clear notice that the stop is ahead, both of which minimize the intrusiveness of the checkpoint. Id. Relevant to the seventh factor, concerning the length and nature of the detention, the Court stated that the methods for detecting intoxication at the checkpoint should be conducted in a swift manner serving the dual purpose of minimizing the intrusiveness of the checkpoint, while seeking to avoid traffic hazards caused by large backups. Id. at 1346. The advanced publicity consideration of the eighth Ingersoll factor relates to reducing intrusiveness of the roadblock into the lives of drivers, while increasing the deterrent effect of the roadblock by putting driver’s on notice that they may be evaluated for intoxication if they choose to drink before driving.

         The fourth of the Ingersoll factor concerns the reasonableness of the checkpoint’s location. The Court explained that, in order to reduce the intrusiveness of the checkpoint and ensure that the underlying purpose of safety is being served, a checkpoint should be clearly visible to motorists in order to reduce surprise, and be set up only in an area where the checkpoint would be most effective. Id. at 1343-1344. To this end, the Court noted that, as to the roadblock at issue in the Ingersoll, the intrusion presented by the checkpoint was substantially minimized by sufficient notice, so as to allow a driver an opportunity, “to avoid the checkpoint altogether”, whereby no vehicle was to be stopped on the sole basis of such avoidance. Id. at 1344-1345, 1326.

            The Ingersoll Court thus determined that reducing the checkpoint’s intrusion into drivers’ lives, enhancing the effectiveness of the roadblocks in achieving its purpose, minimizing arbitrary or capricious enforcement, and ensuring driver safety are all important principles of the Ingersoll factors. An opportunity to choose to avoid the checkpoint, and a right to be permitted to do so without being pulled over by police on that basis alone was significant in the Court’s finding that the checkpoints at issue in the Ingersoll case had minimized the intrusiveness of the roadblocks for purposes of the Fourth Amendment.

Challenging a DUI Checkpoint Resulting in an Arrest under Ingersoll

Courts will balance the eight factors above to determine the reasonableness of a given checkpoint under the considerations of Ingersoll – that is to protect public safety, not simply to make arrests. If you have been arrested for a DUI at a checkpoint, you require a skilled criminal defense lawyer who can make the best arguments for your case under the Ingersoll factors and facts of your situation. At Honeychurch & Giambona, we have defended many clients charged with DUIs after being arrested at DUI checkpoints in the Solano County communities of Fairfield, Green Valley, Vacaville, Benicia, Vallejo, Dixon, or Rio Vista, or in  Napa and Yolo Counties, and have achieved outstanding results. Call our office today at 707-429-3111 and schedule a free consultation with one of our attorneys to discuss how we may be able to best exercise your rights to achieve the best result for your case.


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