Many people may believe that a person is charged immediately after a drunk driving investigation in Minnesota. That is true some of the time, however, many factors may arise that delay the charges. A felony DWI, an investigation into a criminal vehicular operation offense, and other DWI investigations can take days, weeks, or more as prosecutors pore over the evidence in deciding what charges to bring. DWI investigations involving toxicology testing of blood or urine samples can create significant delays in charging.