There is no more savvy politician in the entire city. Nothing sticks to him. He knows exactly how to handle every conflict, every minor or major scandal, what to say and what crowd to say it in front of.
Yes, the Sheriff is a powerful office and a difficult one from which to dislodge anyone. But Gusman has taken on more criticism than most local officials (deservedly so, too!) and has often been at odds with a fairly powerful and popular mayor. The dude keeps on keeping on. More than that, even, he generally gets his way most of the time. You almost have to admire it. Almost.