Pompeius, himself a brave soldier, spared the prisoners as far as he might and could; but he was too pusillanimous and in too awkward a position to prevent or even to punish all atrocities of this sort, as it became him as commander-in-chief to do.

Marcus Cato, the only man who at least carried moral consistency into the struggle, attempted with more energy to check such proceedings; he induced the emigrant senate to prohibit by a special decree the pillage of subject towns and the putting to death of a burgess otherwise than in battle.
The able Marcus Marcellus had similar views.

No one, indeed, knew better than Cato and Marcellus that the extreme party would carry out their saving deeds, if necessary, in defiance of all decrees of the senate.

But if even now, when they had still to regard considerations of prudence, the rage of the ultras could not be tamed, people might prepare themselves after the victory for a reign of terror from which Marius and Sulla themselves would have turned away with horror; and we can understand why Cato, according to his own confession, was more afraid of the victory than of the defeat of his own party.
The Preparations for War The management of the military preparations in the Macedonian camp was in the hands of Pompeius the commander-in-chief.

His position, always troublesome and galling, had become still worse through the unfortunate events of 705.