Virtually every major city and/or entire counties in the U.S., as well as a growing number of international municipalities, have some form of 'pooper scooper' or 'good neighbor' law outlining a pet owners' responsibility to pick up after their dog(s). In fact, the issue is so serious in Germany and England, that dog owners are even required to have their pet's DNA on record. In the U.S., fines for not cleaning up can range from $50 to $2,000 for multiple infractions!
Do your part

Orig Link: http://www.nysun.com/new-york/lehner-known-for-pooper-scooper-law/79867/
August 1, 1978 marks the country's first 'Pooper-Scooper Law'...
161.03 of the New York City Health Code a) A person who owns, possesses or controls a dog, cat or other animal shall not permit the animal to commit a nuisance on a sidewalk of any public place, on a floor, wall, stairway or roof of any public or private premises used in common by the public, or on a fence, wall or stairway of a building abutting on a public place.