A federal judge ruled that the state of Tennessee cannot revoke driver licenses for those who cannot afford to pay their court costs, and must reinstate those previously revoked. The State has appealed the decision.
A breathalyzer does not actually measure blood alcohol content or concentration, which would require a blood sample. There are big differences between the small handheld breathalyzers used in the field, and the larger devices at police stations. Small breathalyzers may justify an arrest, but may not be admissible evidence in court. So how does it work?