There is a special reason for this pardon. This sheriff is a bad guy and it only makes the President look like he is biased against Hispanics-- including legal citizens so I cannot see Trump making himself look like he is discriminating against hispanics. This is to try to show Flynn and Manafort and others that they should not be turned or cut deals with the FBI that hurt Trump because he will use the power to pardon them and dodge the Department of Justice requirements.