DC Breath Test Process

The process of conducting a breath test in a DC DUI case can occur in several different ways and in several different places. If you have been pulled over, it is extremely important to your case to contact an attorney as early as possible in the DC DUI breath test process.

Roadside Breath Tests

The police must follow certain procedures in order for them to get a breath test from someone in DC. Before a person is arrested, a police officer might ask the person to submit to a roadside breath test or a portable breath test. Those are typically referred to as RBTs or PBTs.

The roadside or portable breath tests are not considered to be legally admissible evidence in court. This is because roadside breath tests do not have the same level of calibration and accuracy testing as the breathalyzer machine that the police have at the police station.

A person may be asked to submit a roadside breath test on the street and, after they are arrested, be asked to submit a second breath test at the station.

At the Station

Police are required to follow certain procedures during the breath test process at a DC police station to make sure that the breath sample they are testing is reliable and may be admissible in court.

The most important of those procedures is a 20-minute observation period of a person that the police are required to conduct prior to asking them to submit a breath test. That observation period is to see if the suspect belches, regurgitates, or does anything that could bring alcohol up from the stomach into the person’s mouth.

Having that excessive amount of alcohol in the mouth could throw off the result of the breathalyzer and cause the breathalyzer to produce a blood alcohol concentration reading that is much higher than a person’s actual blood alcohol concentration.

If the police do not perform the 20-minute observation, that could cast doubt on the reliability of any results produced from the breathalyzer machine. The result is still legally admissible, however, a defense attorney could then challenge the result of the breathalyzer test.

Purpose of a Breathalyzer

Breathalyzer tests are the easiest and cheapest way for prosecutors to get evidence against a driver that they suspect of driving under the influence. The other evidence in DUI cases, such as field sobriety tests or observations of police officers are more easily subject to challenge by defense lawyers and are considerably less reliable than a properly calibrated and tested breathalyzer machine.

Since the laws in D.C. and in most of the country are making it easier for police to obtain breath samples from drivers that they suspect to be driving under the influence, it is greatly beneficial for prosecutors to secure convictions in these cases.


At the police officers’ discretion, if a person is intoxicated to the point where they could be suffering from alcohol poisoning, the police will often take a person to a hospital for treatment. There, they can ask the hospital staff to conduct a breathalyzer test or a blood draw. Blood can only be drawn by a medical professional, not a police officer.

Following certain legal channels, the police would have the ability to get the results. In most circumstances, however, the police have the ability to ask a person to submit to a breath test and would do so at the police station after a person has been arrested.

A person should have an attorney to offer advice and support throughout every step of the breath test process in DC, so call a DUI lawyer as soon as possible.