Off-duty cops in two counties in Alabama spent the weekend collecting saliva and blood samples from drivers at roadblocks.

According to Lt. Freddie Turrentine with the St. Clair County Sheriff’s Department, drivers were asked to voluntarily offer samples of their saliva and blood for a study being conducted by the Pacific Institute for Research and Evaluation.

The drivers were compensated for their samples.

“They’ve got big signs up that says ‘paid volunteer survey’ and if they want to participate they pull over there and they ask them questions and if they are willing to give them a mouth swab they give them $10 and if they are willing to give them a blood sample they give them $50. And if they don’t do anything they drive off,” Turrentine explained to The Daily Caller.

Turrentine said that St. Clair County had five roadblocks from Friday afternoon through the early morning hours of Sunday. He added that Bibb County also had roadblocks of this kind.

Turrentine said that Alabama Department of Economic and Community Affairs asked the county to participate and that the funding for the study is coming from the National Highway Safety Administration.

“What they are trying to do is 60 sites across the country,” he said, explaining the study will be conducted from June to October and is meant to get a better understanding of inebriation patterns. (SEE ALSO: IRS seeks to buy hidden cameras, surveillance equipment)

“They are trying to get 75,000 participants with anonymous donations of blood — and they don’t know whose blood or whose swab it is — and they are trying to say, ‘OK, after this hour at night, out of these 75,000 people 10 percent of them had alcohol in their blood or 12 percent of them had some kind of narcotic in their blood. That is all they’re doing, for impaired driving,'” he explained.

Turrentine said he did not know how many people deputies sampled over the weekend but said that St. Clair County had completed its portion of the study and would not be putting up more roadblocks of that kind. He added that this was not the first time the Pacific Institute for Research and Evaluation had conducted a study in the county. The last such test was in 2007.

The Pacific Institute for Research and Evaluation did not immediately respond to request for comment, nor did the Alabama Department of Economic and Community Affairs.

The incident did cause a stir on social media with people voicing concern about the roadblocks.

Update — Tuesday 12:47 p.m. EST: After publication of this article, Bibb County Sheriff Keith Hannah offered more details about the roadblocks in his county Tuesday. Hannah told TheDC that there were five roadblocks in Bibb County this weekend. He stressed that the samples were given voluntarily and that this was not the first time the county had participated in a study of this kind.

“It was a voluntary thing and they were compensated if they gave a DNA sample or a blood sample. The study group compensated them for it. If the motorist wanted to participate they could. If they wanted to go on, they were free to do so,” Hannah said Tuesday.

Update — June 19: The National Highway Traffic Safety Administration responded to The Daily Caller’s inquiry with more information about the study.

“The National Highway Traffic Safety Administration (NHTSA) has been regularly conducting the National Roadside Survey of Alcohol and Drugged Driving in communities across the country for over 40 years. The survey provides useful data about alcohol and drug use by drivers, and participation is completely voluntary and anonymous. More than 60 communities across the country will participate this year. NHTSA always works closely with state and local safety officials and local law enforcement to conduct these surveys as we work to better inform our efforts to reduce drunk and drugged driving. In 2007, the study was expanded to include the voluntary collection of saliva and blood samples as a means for collecting data on illegal and prescription drug use by drivers. Saliva was collected using the Quantisal(tm) oral fluid collection device. Blood samples were collected in gray-top glass test tubes. The samples were then properly shipped to the Immunalysis Corporation laboratory in Pomona, California for drug analysis. The laboratory does not conduct any kind of DNA testing and does not have the capability or equipment to do so. Further, participants who provided samples did so voluntarily and anonymously. There is no way to match the saliva or blood samples with the individual that provided it. Detailed information regarding the survey and collection sample methodology can be accessed here: http://www.nhtsa.gov/staticfiles/nti/pdf/811237.pdf The survey is conducted in about 300 locations across the nation and will involve 8,000 or more drivers, each of whom participate voluntarily and are compensated for their cooperation. The cost of planning, conducting and analyzing the survey total about $7.9 million over a three-year period.”

(H/T Matt Murphy)

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