Modesto area police agencies readily say that drunken drivers aren't their only targets when they set up DUI checkpoints.
They're also aiming to curb unlicensed drivers, who police say are safety threats for others.
That's why so many vehicles are towed at driving-under-the-influence checkpoints compared with the number of arrests they achieve, officers say.
Ceres police Sgt. Danny Vierra said a lot of drivers leave the scene of a crash, which is a felony, because they don't have a license or insurance.
"We definitely believe hit-and-run accidents have a correlation with unlicensed drivers," said Vierra, who coordinates the department's checkpoints. "I think (the checkpoints) are a good way to attack both problems."
Vierra and other local officials are responding to a recent California Watch investigation that found police agencies statewide are raking in millions of dollars in towing fees while officers earn overtime to staff checkpoints that record few DUI arrests.
California Watch, a nonprofit investigative news outlet, found that cities with higher populations of Latino residents tended to have greater numbers of cars towed at checkpoints, a correlation that officials attributed to the likelihood that some of those cars belong to illegal immigrants.
For example, in Modesto where the population is 34 percent Latino, officers towed eight vehicles for every DUI arrest during four checkpoints in fiscal year 2008-09.
In Ceres, where the population is 50 percent Latino, officers towed about 20 vehicles for every DUI arrest during two checkpoints, according to the data collected by California Watch.
Its three-month analysis, however, did not find evidence that police departments set up checkpoints to target Latino drivers.
Local police agencies said they choose checkpoint locations based on how many DUI-related crashes and arrests occur in that area, along with the amount of traffic on a given street. The agencies rotate the locations for the checkpoints.
The California Watch study also found tow-aways from checkpoints in 2009 statewide generated an estimated $40 million in towing fees and police fines, revenue that cities divide with towing firms.
Modesto police Lt. Scott Blom said towing vehicles is not an effort to generate money. He said officers can't let an unlicensed driver leave in the vehicle, because the department would be responsible.
"We can't just say 'never mind, here are the keys,' " said Blom, who supervises the department's traffic unit. "When they go down the street and get in a wreck, it's our fault."
One in every 10 drivers screened at Riverbank checkpoints doesn't have a valid license, said Stanislaus County sheriff's Sgt. Vince Kimbrough, whose duties include overseeing traffic enforcement in Riverbank.
Suspended license, 3 DUIs
At a Riverbank checkpoint this month, Kimbrough said officers encountered a woman driving with a suspended license because of a DUI conviction. Her license had been suspended twice before for two other DUI convictions.
"And she's still driving a vehicle with no insurance, because she can't get insurance without a license," Kimbrough said. "We're not about towing away vehicles. It's about correcting bad driving behavior."
California Watch analyzed data documenting the results from every checkpoint that received state funding the past two years.
Ceres, Modesto, Riverbank and Ripon police departments were listed in that data. Ripon police officials were not available to comment for this report.
Officers statewide received about $30 million in overtime pay for the DUI crackdowns funded by the state Office of Traffic Safety, according to the study.
Modesto police received $73,000 in state grants to fund checkpoints this year and $37,000 for saturation patrols, in which officers drive around looking for impaired drivers.
About $3,000 is needed to fund a Modesto police checkpoint. Blom said the department plans to conduct about 20 checkpoints this year.
The local police agencies say they can't afford to pull officers from regular patrol duty to operate the checkpoints. They don't want to reduce patrol staffing, so they're forced to have officers earning overtime at the checkpoints.
In some cases, officers assigned to DUI units can work at the checkpoints earning their base salary, but local police officials say that's a rarity.
Blom said Modesto police has a minimum of eight officers at each checkpoint but prefers to have 10 to 12 officers.
When drunken drivers are arrested, officers have to step away to start paperwork and take the suspect to jail.
"You got a lot of things going on at once, and you have to keep the line moving," Blom said. "We're dealing with a whole bunch of cars moving through the checkpoint."
According to the study, an average of 18 officers worked at each checkpoint statewide. The federal traffic safety agency advises that police can set up checkpoints with as few as six officers.
"I don't see how you can do a checkpoint with six officers," said Vierra of the Ceres Police Department, which has 10 to 13 officers working at each checkpoint.
Ceres police received an $80,000 state grant this year for anti-DUI operations, and $27,000 from the grant will be used for checkpoints.
Ceres police will conduct four checkpoints this year and spend about $3,500 to $5,000 on each checkpoint.
Riverbank police services received $150,000 in state grants for DUI enforcement operations, including sobriety checkpoints and saturation patrols.
Kimbrough said Riverbank police has 18 checkpoints scheduled this year, and it takes $3,200 to $3,400 to fund a checkpoint.
Sometimes, Riverbank police will decide not to tow a vehicle from an unlicensed driver. At a recent checkpoint, Kimbrough said, officers came across a man driving with a license that had expired six days earlier.
The driver admitted he had forgotten about the expiration date, so Kimbrough said they had the man's wife pick up the vehicle instead of towing it.
"It's not a money venture," Kimbrough said. "It's about educating the public."
Bee staff writer Rosalio Ahumada can be reached at firstname.lastname@example.org or 578-2394.