Judgment and motor skills are the first be affected by alcohol. This could involve weaving, weaving across lane lines, straddling a lane line, swerving, turning with an unusually wide radius, drifting, or almost striking a vehicle or other object Speed and Braking Problems. This includes driving in opposing lanes or wrong way on one-way street, slow response to traffic signals, slow or failure to respond to officer's signals, stopping in lane for no apparent reason, driving without headlights at night, failure to signal or signaling that is inconsistent with action. Do not attempt to stop the vehicle. It would be prudent to try and steer clear of the car in question and you may even want to take down the license plate number and vehicle description and report it to the police.
Motivations are usually unclear.
In fact, many people who decide to drive after consuming alcohol do not, at the time, consider their actions to be risky or potentially life threatening. Young drivers are considered less likely than any other age group to change their drinking and driving behavior. Alarmingly, about one third of all drivers arrested or convicted of DUI each year are repeat offenders. There are several new prevention strategies that hold great potential to reduce the incidence of drunk driving. Some researchers believe that lowering the legal limit of the BAC to 0.08 would reduce alcohol-related fatalities by as much as eight percent.