Breathalyzer Law and Legal Definition

A breathalyzer is a chemical test administered to a person to detect the presence of alcohol in their body in order to determine if they are legally intoxicated. The test is commonly given by a police officer to a person suspected of drunk driving. The results of a breathalyzer test may be invalidated if the officer cannot testify to the proper working order and calibration of the breathalyzer. Breathalyzer maintenance is conducted according to state regulations, which vary by state. The person performing the maintenance may be required to be certified under state law.

Most states have implied consent laws, which vary by state, that assume the consent to a breathalyzer test is given by the act of driving on public roads. Failure to take the breathalyzer test when requested usually leads to stiffer penalties and automatic revocation of driving privileges. Results of a breathalyzer test are admissible in court.