By JULIE HIRSCHFELD DAVIS Police chiefs are backing appeals court judge Sonia Sotomayor's bid to become a Supreme Court justice.International Association of Police Chiefs President Russell B. Laine says Sotomayor has outstanding qualifications for the job. Laine voiced his organization's support in a letter to Vermont Democrat Patrick Leahy, the Senate Judiciary Committee chairman.Laine says Sotomayor has shown understanding and appreciation of the challenges facing law-enforcement officers, and dedication to keeping communities safe.With his group's nod, Sotomayor has the backing of several of the nation's major law-enforcement organizations.