Morally, I agree with you. My former prime minister is in jail for graft, theft essentially. He will spend less time in prison (though fortunately he is at least serving some) than a common thief even though the damage he has done is imesurably greater.

The reason I argue the opposite (OP) is for practical rather than moral reasons. Morals are a luxury. Systemic stability is at stake and is a requisite for any rule of law.

That said, prosecuting legislators and/or political executives for ilegal legislation is far too dangerous, essentially merging all branches of government.