If a president murdered one of his employees who was threatening to blow the whistle on some corruption?

and he shot this subordinate to death point blank right there in the white house......could the president just pardon himself for the shooting/murder and the other corruption too? and then simply go about his business? Evenif he is impeached...and convicted....can't he just pardon himself and then say....Ho hum....and then NEXT ORDER OF BUSINESS !!!!!