In December 1792, Maximilien Robespierre, then an ordinary deputy to the National Convention, addressed the convention on what should be done with the king, Louis XVI:

“What is the conduct prescribed by sound policy to cement the republic? It is to engrave deeply, into all hearts, contempt for royalty and to strike terror into the partisans of the king. To place his crime before the world as a problem… to place an immeasurable space between the memory of what he was and the title of ‘Citizen’, is the very way to make him most dangerous to liberty.

Louis is dethroned by his crimes. He conspired against the Republic: either he is condemned or the Republic is not acquitted. To propose the trial of Louis XVI is to question the revolution. If he may be tried, he may be acquitted; if he may be acquitted, he may be innocent. But if he is innocent, what becomes of the revolution? If he is innocent, what are we but his calumniators [false accusers]?

The coalition is just, his imprisonment is a crime, all the patriots are guilty; and the great cause, which for so many centuries has been debated between crime and virtue between liberty and tyranny, is finally decided in favour of crime and despotism!…

There is another difficulty – to what punishment shall we condemn him? The punishment of death is too cruel, says one. No, says another life is crueller still and we must condemn him to live. Advocates, is it from pity or from cruelty you wish to annul the punishment of crimes? For myself, I abhor the penalty of death; I neither love nor hate Louis, I hate nothing but his crimes.

I demanded the abolition of capital punishment in the National Constituent Assembly… But you who never thought this mercy pardonable, by what fatality are you reminded of your humanity to plead the cause of the greatest of criminals? You ask an exception from the punishment of death for him who alone could render it legitimate! A dethroned king in the very heart of a Republic not yet cemented! A king, whose very name draws foreign war on the nation! Neither prison nor exile can make his an innocent existence. It is with regret I pronounce the fatal truth: Louis must perish rather than 100,000 virtuous citizens! Louis must perish because our country must live.”