1. Except as otherwise provided in this section, a person "is prosecuted" for an offense, within the meaning of section 40.20, when he is charged therewith by an accusatory instrument filed in a court of this state or of any jurisdiction within the United States, and when the action either:

1. (a) Terminates in a conviction upon a plea of guilty; or
2. (b) Proceeds to the trial stage and a jury has been impaneled and sworn or, in the case of a trial by the court without a jury, a witness is sworn.

2. Despite the occurrence of proceedings specified in subdivision one, a person is not deemed to have been prosecuted for an offense, within the meaning of section 40.20, when:

1. (a) Such prosecution occurred in a court which lacked jurisdiction over the defendant or the offense; or
2. (b) Such prosecution was for a lesser offense than could have been charged under the facts of the case, and the prosecution was procured by the defendant, without the knowledge of the appropriate prosecutor, for the purpose of avoiding prosecution for a greater offense.