Wisconsin drivers who have been stopped for suspected drunk driving may have been subjected to breathalyzer testing by their investigating officers. Others may have been required to give blood to determine their blood alcohol content. Both breathalyzer and blood tests give authorities evidence of a driver's BAC which is used to determine if they were driving above or below the state's legal limit.
In some cases when a suspected drunk driver is convicted of DUI or OWI he is required to install an ignition interlock device in his vehicle. These devices require drivers to blow into them before the car can start. If a driver blows and the device detects alcohol, the car will not operate.
According to the Wisconsin Department of Transportation, ignition interlock devices (also known as IIDs) are required for drivers who are convicted of first time OWI with BACs above .15. Additionally, drivers with more than one alcohol-related driving offense are required to get IIDs, as well as individuals who exercise their right to not submit to breath or blood testing. There are exceptions to this rule, and attorneys who practice DUI defense can provide more information to interested parties.
Drivers who must install IIDs generally lease the devices. At present there are four different models of IIDs that Wisconsin courts accept. In most cases, drivers have around two weeks after the court orders them to get IIDs to install the devices. Drivers must keep the devices in their vehicles for the duration of the court's orders.
Ignition interlock devices can subject drivers to stress and stigma. Though courts must follow the law when the facts of a case requires an IID to be installed, an individual facing DUI and OWI charges has rights. Attorneys who work in the DUI defense field are trained to understand the exceptions and nuances of IID requirements and Wisconsin's drunk driving laws.
Source: Wisconsin Department of Transportation, "Alcohol and chemical testing," accessed on July 27, 2014