after a plea of guilty under section 845(b) of this title (article 45(b));

by a military judge in a court-martial with a military judge alone, under section 816 of this title (article 16); or

in a court-martial with members under section 816 of this title (article 16), by the concurrence of at least three-fourths of the members present when the vote is taken.

Except as provided in subsection (a) and in paragraph (2), all matters to be decided by members of a general or special court-martial shall be determined by a majority vote, but a reconsideration of a finding of guilty or reconsideration of a sentence, with a view toward decreasing the sentence, may be made by any lesser vote which indicates that the reconsideration is not opposed by the number of votes required for that finding or sentence.

A sentence of death requires (A) a unanimous finding of guilty of an offense in this chapter expressly made punishable by death and (B) a unanimous determination by the members that the sentence for that offense shall include death. All other sentences imposed by members shall be determined by the concurrence of at least three-fourths of the members present when the vote is taken.