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The defendant demanded a trial as the best forum for proving the constitutionality of secession, and the government requested numerous delays to prepare its case. Although the indictment was finished in March 1868, the Johnson impeachment further delayed the case. The court finally heard preliminary motions in December 1868, when the defense asked for a dismissal claiming that the Fourteenth Amendment to the U.S. Constitution already punished Davis by preventing him from holding public office in the future and that further prosecution and punishment would violate the double jeopardy restriction of the Fifth Amendment. The court divided in its official opinion and certified the question to the United States Supreme Court. Fearing the court would rule in favor of Davis, Johnson released an amnesty proclamation on December 25, 1868, issuing a pardon to all persons who had participated in the rebellion.