Number 341 January 2008

Traffic Safety Facts

Traffic Tech – Technology Transfer Series

U.S. Department of Transportation 1200 New Jersey Avenue SE., Washington, DC 20590

National Highway Traffic Safety Administration

The National Highway Traffic Safety Administration

(NHTSA) has been studying the DWI arrest and adjudication process, including breath test refusals. This

Traffic Tech reports on one promising approach for

reducing refusals - the use of warrants for obtaining

blood samples from drivers arrested for DWI.

As part of the evidence-gathering for an impaired driving investigation, an officer typically requests a breath

sample from the driver to determine the person’s blood

alcohol concentration (BAC). Not all drivers comply

with these requests even though all States have some

form of an implied consent law, which provides that as

part of accepting the agreement for receiving a license,

a driver agrees to provide a breath, blood, or urine sample when properly requested.

In 2005, NHTSA released a study that examined States’

breath test refusal rates (see Traffic Tech #300). Overall, the rates varied dramatically among States, from

5% to 85%. The study included interviews in five States

to learn about the refusal issue and identify potential

solutions for high rates. One strategy that emerged is

the use of warrants to obtain blood samples from drivers who refuse to provide breath samples.

To learn more about this approach, NHTSA contracted

with the Preusser Research Group (PRG) to examine the

use of warrants to obtain blood samples from drivers

arrested for DWI. Our objective was to examine the policies, procedures, and experiences in selected States.

The researchers conducted case studies in Arizona,

Michigan, Oregon, and Utah. They obtained additional information from California and Nevada, two

States in which officers can obtain blood samples

without warrants.

Not all of the jurisdictions within our selected States

seek warrants; nor do officers use this approach in

all impaired driving cases. Officers in other States

may also seek warrants in DWI cases, although at

this time it is not considered to be common practice

across the country.

In each case study State, PRG conducted interviews

with about 15 people, including officers, prosecutors,

defense attorneys, and judges. These individuals provided information on policies and procedures, as well

as opinions on the warrant process.

Procedures for Requesting a Warrant

The procedures vary between States. However, in general if a driver arrested for DWI has refused to provide

a breath sample, an officer can call an available judge

(the jurisdictions typically have a few judges “on call”

at all times of the day and night) and request a warrant. The judge then swears in the officer over the

phone, and the officer faxes the warrant forms to the

judge. The judge then reviews the information and can

sign the warrant and fax it back to the officer. In some

jurisdictions, if the officer does not have access to a

fax, warrants can be obtained by phone. The officer

then takes the arrested driver to a physician, nurse, or

phlebotomist (a person trained in drawing blood) to

obtain the sample. In a few jurisdictions, law enforcement officers are trained as phlebotomists.

Conclusions

In general, the people interviewed for this study were

supportive of the use of warrants for blood draws, even

when the use of a warrant required additional processing time and (forjudges) late-night calls. Many strongly

believe that the BAC is a valuable piece of evidence and

The Use of Warrants for Blood Draws: One 

Promising Solution to the Issue of Breath Test 

Refusals in DWI Cases
TRAFFIC TECH is a publication to disseminate information about

traffic safety programs, including evaluations, innovative programs, and new publications. Feel free to copy it as you wish. If you

would like to receive a copy, contact Patricia Ellison-Potter, Ph.D.,

Editor, fax 202-366-7096, e-mail: traffic.tech@dot.gov.

can make the difference between a guilty plea and a

trial. And BAC evidence is critical in the prosecution of

“high” DWI cases (when there are enhanced sanctions

for BACs over a threshold such as .15).

A disadvantage of the warrant system is that it can

take 2 hours for the officer to complete forms, contact

a judge and wait for warrant approval, and transport

the offender for the blood draw and then wait for the

sample. Much of this time can be reduced if, as in Arizona and Utah, officers are trained as phlebotomists.

Another issue with blood draws, although considered

rare, is the possibility of a medical complication. Not all

judges support the use of warrants for impaired driving crimes.

There are monetary costs involved with obtaining

blood samples, either paying qualified people to draw

the blood sample, or phlebotomy training for officers. There are also the costs of blood kits and lab fees

for analyzing the samples. These costs could be paid

through offender fees.

1200 New Jersey Avenue SE., NTI-130

Washington, DC 20590

The use of warrants to obtain blood samples appears

to be a promising strategy in obtaining BAC evidence

in DWI cases. NHTSA is continuing to examine this

topic with research on the effect of refusals on DWI

prosecution, and whether the use of warrants can

reduce refusals.

NHTSA also has a Research Note available that both

summarizes the information from this study, as well as

providing data on States’ refusal rates.

How to Order: To order the report, Use of Warrants for 

Breath Test Refusal: Case Studies, or to order the research

note Breath Test Refusals write to the Office of Behavioral

Research, NHTSA, NTI-130, 1200 New Jersey Avenue

SE., Washington, DC, 20590, fax 202-366-7096, or download from www.nhtsa.dot.gov. Amy Berning was the

project manager for this study.