Even if your blood alcohol level is only 0.03 or lower, the police can still charge you with Operating While Intoxicated. The charge is left to the prosecutor's discretion, leaving you to challenge their decision in court. Even the police officer lacks discretion once the decision to arrest has been made. Police officers are instructed that, "[u]nder no circumstances should you charge the suspect with a lesser offense instead of DWI if there is probable cause to believe that DWI has been committed. Any reduction of DWI to a lesser charge is the responsibility of the prosecutor or judge." [NHTSA DWI Detection and Standardized Field Sobriety Testing, VII-10; underline in original.]
The ever decreasing permissible blood alcohol level was intended to "crack down" on drunk drivers. Instead, it has criminalized thousands of otherwise law abiding citizens, threatening them with steep fines and costs, probation, mandatory counseling and alcohol "awareness" programs, community service and even jail. Meanwhile, alcohol-related traffic fatalities have actually increased during the last few years!