The Senators in question were closely embedded with the powerful institutions of the Republic, yet chose to murder the Gracchi without the approval of those institutions. Arguably, the participation and appropriate actions of the law-making and executive institutions of the Republic could render a murder technically lawful, even though it contradicted the law at the time of the deed.

As the Senators bothered with no such niceties, not only was it a blow against the ambitions of the poor to do such terrible things as “not starve to death” and “not be reduced to slaves in their own country”, but also a very pointed message to the institutions of the Republic itself - “We, the conservatives, consider ourselves to be the ultimate power here, not the Republic or the laws it proclaims.”

Whether that justifies the inclusion of ‘illegally’ to ‘murdered’ is a matter of taste, lmao.