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(619) 326-8161
The Law Office of


(619) 326-8161

San Diego DUI Checkpoints

As we near kick off a new year, I wanted to give my readers a primer on one of the hottest DUI topics out there, checkpoints. As San Diegans, we see these used pretty much every weekend by the police, in Pacific Beach, downtown in the Gaslamp, Chula Vista and usually in East County. I am not familiar with any checkpoints set up in North County with any regularity. Occasionally I’ll hear of one in Poway.

History of DUI Checkpoints

Checkpoints were approved by the California Supreme Court in Ingersoll v. Palmer (1987) 43 Cal.3d 1321, as long as they were carried out pursuant to “strict guidelines.” The court went on to conclude that checkpoints can comply with the Constitution if they follow these guidelines. Later in the Michigan State Police v Sitz case, (1990) 496 U.S. 444, the use of DUI checkpoints was essentially confirmed for use across the nation.

The Requirements of Checkpoints

As mentioned above, within the Ingersoll case, requirements were set forth for the Constitutionality of a DUI Checkpoint in California.  The main attack on a DUI checkpoint would be for the defense attorney to call in to question the sufficiency of each requirement. I will break down a few of the most common attacks in this blog post. 

The Ingersoll guidelines fall under the following general headings:

1.       Decision Making at the Supervisory Level

An often overlooked challenge in San Diego DUI Checkpoint cases is a lack of decision making at a supervisory level. Usually a letter is sent from the traffic captain to two Sergeants and they are tasked with coming up with the plan for the DUI checkpoint. It is arguable these sergeants are not supervisory personnel. There is a case that addresses this point. 

In People v. Alvarado (2011) 193 Cal.App.4th Supp. 13, the Alvardo Court compared the facts of the present case to the requirements set out in Ingersoll and determined that the prosecution failed to demonstrate the DUI checkpoint was conducted in a Constitutional manner. Specifically it stated: the role of Supervisory Personnel was insufficient because the evidence showed that a sergeant approved the procedures used in the checkpoint, and these procedures were different from those specified by the captain. Now when the captain doesn’t set out the procedures and leaves it to the sergeant to make those decisions, are supervisory personnel making the decisions?

 2.       Limits on Discretion of Field Officers

Once the procedures are set out by supervisory personnel, the officers in the field are not free to deviate from these procedures. They essentially are robots who are to follow the directives set out for them. Ingersoll stated a motorist should not be subject to the unbridled discretion of the officer in the field as to who is to be stopped. This means a neutral formula, such as every driver or every fourth, seventh or eleventh driver, should be used. To allow officers to stop any driver or car or to change the formula used when there is no legitimate basis for the determination would be the exact kind of unconstrained and standardless discretion the United State Supreme Court sought to eliminate in its decision. There must be a neutral mathematical selection used.

The most common method employed by the San Diego Police is a “fill the pocket” method. This essentially means they have a “pocket” 8-10 cars long. They then fill this pocket with vehicles and once it’s filled they close the pocket and let the other motorists pass. The problem with this method is in the execution. Often as 1 spot opens up, they allow another car to enter and so on. They don’t actually wait for the pocket to completely empty before they fill it up again. They merely fill it as they go.

A Checkpoint packet is available through discovery, and it has a chart illustrating the vehicles detained. A change in method to adjust for traffic flow is neutral as long as there is a formula for the change. What is not allowed is an unjustified change of the neutral formula. If the pattern suddenly changes, an inference of non-neutrality arises making the checkpoint potentially unconstitutional.

3.       Maintenance of Safety Conditions

At all times the proper signage, cone patterns and lights should be employed to keep the public safe.

4.       Reasonable Location

The locations used in San Diego, Gaslamp, Pacific Beach, Chula Vista and East County are typically locations that have a relatively high incidence of DUI arrests. Again all this information is available in the checkpoint packet available through discovery.

5.        Time and Duration

Much like the reasonable location, the DUI checkpoint must be conducted at a reasonable time and for a reasonable duration. The checkpoints in San Diego are usually conducted from late evening to early morning. One thing I often notice is that the checkpoints usually go past their scheduled time. This would be a key argument not only for duration and reasonableness of time but also for a deviation from the procedures set out by supervisory personnel.

Additionally, the initial stop must be minimally intrusive and brief, and then only drivers who exhibit symptoms of impairment are directed to a secondary screening area. Sitz, (1990) and Ingersoll. Where a motorist merely acknowledges to having had a drink or two, but the officer does not detect any sign of impairment (either in the manner of driving or by the operator’s physical manifestations), then there is no constitutional basis for further detention to a secondary screening area.

6.        Indicia of Official Nature of Roadblock

There is usually lights, cones and flares as well as numerous police vehicles at the checkpoint. There is also signage well before the checkpoint to warn of a police checkpoint up ahead. A map of these locations is provided in the checkpoint packet.

7.       Length and Nature of Detention

See the 2nd paragraph of #5.

8.       Advance Publicity

There is great debate in this requirement becasue People v. Banks (1993), held that advance publicity is not an essential element of the constitutionally of a valid drunk driving roadblock. The Court said that although advance publicity remains a factor to consider, the lack of it alone does not render a roadblock unconstitutional.

 Usually within the checkpoint packet they will provide a media release although there is no proof it was actually published by any media.

 The infamous “escape route”

Ingersoll v. Palmer stated the following: “Checkpoint personnel were specifically instructed that drivers were not to be stopped merely for avoiding the checkpoint. The road sign announcing the checkpoint was placed sufficiently in advance of the checkpoint that motorists could choose to avoid the checkpoint.” The Ingersoll court did not specifically enumerate that an escape route is necessary for the DUI checkpoint to be Constitutional, however whether the checkpoint has an escape route is to be used as one of several factors to be considered in determining whether the DUI checkpoint location was reasonable.

 DUI checkpoint cases are some of the most common DUI arrest cases that lawyers face. They can be very specific and detail oriented to defend. A thorough analysis of the information contained in the DUI checkpoint packet is critical information to a San Diego DUI Lawyer‘s ability to defend his/her client against a DUI.