The House Ethics Committee is investigating a sitting Democratic lawmaker over allegations of sexual misconduct.The committee, which acts as the House of Representatives' internal watchdog, announced Monday that it is investigating Rep. Jimmy Gomez, D-Calif., over allegations including "inappropriate sexual contact with a House staffer."He's the latest House lawmaker to be accused of misconduct or harassment in relation to aides on Capitol Hill, an issue that's rocked Congress and forced a new reckoning over rules of engagement for lawmakers in Washington.CAPITOL HILL SEX SCANDALS TRIGGER NEW...