A core reason why you need to enforce anti-corruption rules at the top of government is because they set the tone for everyone else. If the leaders of the federal government are blatantly, wildly corrupt, everybody else looks at that and goes “so why should I follow the rules of they don’t?”
Mardochethics rules for my wife, a community college teacher: ironclad. strictly enforced ethics rules for government: what? lol makes me the joker every time she tells me about turning away a thankful/appreciative student gift because hey, that's quite against the law!