Here there is a "controlling legal" authority - but the odds of McDermott seeing any sanction (e.g., a fine or even jail time) are slim and none.
Go to jail, do not pass go but go directly to jail.
Remember that the left tried to go after Linda Tripp for taping some conversations she was having with Monica Lewinsky.
That said, this illegal act by a member of Congress is not protected by the First Amendment. I say get him out of office now.