During a DUI/DWI stop, the officer will normally ask the driver to take a breath or blood test to determine the amount of alcohol or drugs in the driver's system. The driver's blood alcohol concentration (BAC) or the concentration of drugs in the driver's blood is often used to prove a DUI or DWI in court. However, failure to submit to a chemical test can also have consequences.
Under Maryland's implied consent law, anyone who operates a vehicle within the state is deemed to have consented to a test of the driver's breath or blood. However, this requirement applies only if the driver is legally detained for suspicion of intoxicated driving.
Generally, a driver who does not consent to testing can't be physically forced to test, though some exceptions exist.
License suspension. A driver who refuses a lawful request for chemical testing will be subject to immediate license seizure. Upon refusal, the officer is supposed to take the driver's license, issue a temporary ten-day license, and forward the refusal certification to the Motor Vehicle Administration. Thereafter, drivers who wish to contest the suspension have ten days to request a hearing. If the suspension is affirmed or uncontested, the driver's license will be suspended for 270 days. A driver with a prior intoxicated driving suspension faces a two-year suspension for a refusal.
Ignition interlock program. Drivers suspended due to an intoxicated driving incident (refusal, conviction, or test failure) can apply for the ignition interlock program. Drivers who participate in the program are permitted to drive a motor vehicle equipped with an ignition interlock device (IID). A driver who's suspended for test refusal will generally be eligible for license reinstatement after successfully completing one year with the IID.
Evidentiary uses. As test results are used to prove a DUI in court, some drivers refuse testing with the intent to limit the available evidence showing they were driving under the influence. However, the fact that a driver refused testing is admissible in court and can be considered by the jury in determining guilt.