California Supreme Court uses 8 Guidelines that minimize the intrusiveness on an individual, while balancing needs to keep drunk drivers off the road
The initial establishment and location of California DUI sobriety checkpoints must be decided by supervisory police officers, not officers in the field. This requirement is important to reduce the potential for arbitrary and random enforcement. drivers at California DUI checkpoints. California DUI police must use a neutral mathematical formula, such as every driver, or every third, fifth, or tenth driver to determine who to stop. This requirement takes away the discretion of the individual officer to choose to stop individual drivers without any legitimate basis. California DUI police also must give primary consideration to maintaining safety for motorists and officers. In order to minimize the risk of danger to motorists and police, proper lighting, warning signs and signals, and clearly identifiable official vehicles and personnel are required. The California Drunk Driving checkpoint should only be operated when the traffic volume allows the operation to be conducted safely.
Locations of California DUI roadblocks are regulated - Supervisory officer must choose a location that will be most effective in stopping DUI Drivers
Effective locations include roads which have a high incidence of alcohol-related accidents and California DUI arrests. The time and duration of California DUI sobriety checkpoints are of key importance. Police are expected to exercise good judgment in setting times and durations, with an eye to effectiveness of the operation, and with the safety of motorists in mind. As long as these considerations are in effect, there are no hard and fast rules as to the timing or duration of the California Drunk Driving roadblock. California sobriety checkpoints also must be established with high visibility so that drivers can easily see the nature of the roadblock. The features that promote high visibility include flashing warning lights, adequate lighting, police vehicles, and the presence of uniformed officers. Not only are such factors important for safety reasons, but advance warning will reassure motorists that the stop is duly authorized. Advance notice & escape routes are also required.
California DUI Defense Attorneys can determine whether a California DUI sobriety checkpoint was conducted lawfully
Although the Supreme Court's Ingersoll decision legitimized California Drunk Driving checkpoints, it established strict guidelines under which the roadblocks must be operated. If California DUI law enforcement do not follow the factors set out by the California Supreme Court, the evidence gained as a result of the roadblock may be suppressed as a violation of the Fourth Amendment rights of the motorist and may not be the basis to support a finding of a lawful arrest at a California DMV license suspension hearing.