CONSTITUTION OF BOTSWANA
CHAPTER II - Protection of Fundamental Rights and Freedoms of the Individual (ss 3-19)
10. Provisions to secure protection of law
(5) No person who shows that he or she has been tried by a competent court for a criminal offence and either convicted or acquitted shall again be tried for that offence or for any other criminal offence of which he or she could have been convicted at the trial for that offence, save upon the order of a superior court in the course of appeal or review proceedings relating to the conviction or acquittal.
EDIT.