You suspect two murders. One by dnc and one by rnc. You have video of the dnc one and you don't show it because you lack the other video? You hide the truth

You suspect two murders. One by dnc and one by rnc. You have video of the dnc one and you don't show it because you lack the other video? You hide the truth because it is not fair to the first murder that you don't have proof of the other?