Originally Posted by
gugi
The only problem is that he isn't their employer.
It's the voters in the congressional district, or the state, who can elect a different representative/senator at the end of their term if they aren't happy with how they're doing the job.
Just as an example - this past week the republican voters of Indiana nominated Donald Trump for president and the sitting representative from the 9th congressional district for senator.
The US Constitution is very clear and the Supreme Court has always upheld that the executive branch cannot meddle in the legislative. Trump has to work with Congress, which he understands very well given his recent remarks.