Were the murderers of Thomas Becket ever brought to justice?
They were not legally punished.
On December 29, 1170, four knights, Reginald fitzUrse, Hugh de Morville, William de Tracy, and Richard le Breton, were sent out by royal command to confront Archbishop of Canterbury Thomas Becket about his excommunicating many clergymen.
The confrontation ended when the four knights killed Becket in the cathedral as the monks were chanting vespers.
They were never arrested or charged by the king, but neither did they receive support from him.
They were excommunicated by Pope Alexander, however, regretting their actions, they went to Rome hoping for forgiveness. There, the Pope told them they had to serve as knights in Rome for fourteen years to attone.
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