Illegal? Of course not! Immoral, Unethical, Bad image? So what. Lifetime position. It can't be illegal if the Supremes do it, they are the supreme arbitrator of what is illegal. Just like Congress critters cannot be making stock trades with insider information. They wrote the law on that and it says they cannot be insider traders because they exempted their own actions from the law. See? It can be equally nice to write the law or to be the final interpreter. And it gets even cozier when the law is so complicated that the congress critter never actually reads it, they just trust the industry flak who actually wrote the proposal to explain what it says before congress votes on it.