Who is Sheriff Eagles from The Persian Pickle Club and what is their importance?

Town lawman Sheriff Eagles is genial and perceptive, on first glance a fairly hands off officer of the law but ultimately someone who will stand for little or no nonsense. He is also, as narration reveals late in the book, the brother of Ella Crook, the implication being that he knows full well the truth about her marriage to Ben. A further implication is that he has at least his suspicions about the truth of his death, and that he supports the Pickles in their conspiracy of silence to protect his sister.