A fundamental rule of Constitutional law is that the Double Jeopardy Clause provides that no person shall “be subject to the same offense to be twice put in jeopardy of life or limb.” U.S. Const. amend V. This protection is guaranteed by the Nevada Constitution. This basically means that a person shall not be prosecuted twice for the same offense. According to an unpublished recent opinion (Seay v. The Eighth Judicial District Court of The State of Nevada, et al), this rule applies to DUI cases as well.
In Las Vegas, a first or second DUI arrest is a misdemeanor offense. A third DUI or a DUI causing death or substantial bodily harm is a felony. DUIs are prosecuted in Municipal Court if the DUI arrest is (1) a misdemeanor and (2) within city limits. All felonies are prosecuted in Justice Court. In some cases, a person will be arrested on one date, but be charged with both misdemeanor and felony DUI in two different Courts. Now, under the Seay case, it appears as though the Nevada Supreme Court will dismiss the second case once a person has been convicted in the first case—so long as the charges all stem from the same arrest.
Seay v. The Eighth Judicial District Court of The State of Nevada, et al was an unpublished opinion. As a result, it is not binding legal authority. However, the case provides good insight into the Nevada Supreme Court’s treatment of the issue for similarly situated cases in the future.