Article 18. [Provisions to secure protection of law]
(5) No person who shows that he 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 could have been convicted at the trial for that offence, except upon the order of a superior court in the course of appeal or review proceedings relating to the conviction or acquittal.
(6) No person shall be tried for a criminal offence if he shows that he has been pardoned for that offence.
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