If there's no law aimed specifically at dogs, a general nuisance or noise ordinance makes the owner responsible. And someone who allows a dog to bark after numerous warnings from police may be arrested for disturbing the peace. To find out what the law is where you live, go to a law library and check the state statutes and city or county ordinances yourself. Or call the local animal control agency or city attorney. Ask animal control authorities to enforce local noise laws.
Some cities have special programs to handle dog complaints.
Call the police, if you think a criminal law is being violated. Generally, police aren't too interested in barking dog problems. And summoning a police cruiser to a neighbor's house obviously will not improve your already-strained relations. But if nothing else works, and the relationship with your neighbor is shot anyway, give the police a try. Shows you how to succeed using this quick, fair and inexpensive alternative to courtroom battles.