Follows the law
That’s right, the commander and chief are not above the law while they are in office, they still need to abide by the rules like the rest of us. If they do not, then they can be impeached and thrown out of the White House, then tried for whatever crime they committed.
How many countries on earth have you ever seen the leader get kicked out and then thrown into jail? Alright, so it basically never happens, they still can do more or less whatever they want to. But with enough pressure applied, if they commit a crime, it could end their career or even worse.