Final answer:
All six jurors in a jury of six must concur to render a verdict when the punishment may be confinement at hard labor. The unanimity ensures a collective agreement and a thorough deliberation process among jurors.
Step-by-step explanation:
When punishment may be confinement at hard labor, and the defendant is tried by a jury composed of six jurors, all six of the jurors must concur to render a verdict. In the United States, it's a well-established principle that the decision of the jury in criminal trials should be unanimous unless otherwise specified by law. This means that if a jury is composed of six jurors, each and every one of them must agree on the verdict for it to be rendered as the final judgement in a case. The requirement for a unanimous verdict helps to prevent wrongful convictions and ensures that the decision is the result of collective agreement and thorough deliberation among the jurors.