During the 1860's and 1870's, Henry Bergh of New York succeeded in establishing the first significant anti-cruelty laws in the United States, and the first humane society, called the American Society for the Prevention of Cruelty to Animals. (Sydney H. Coleman, Humane Society Leaders In America, 33-35 (1924).)
The constitution of the ASPCA stated that its purpose was "[t]o provide effective means for the prevention of cruelty to animals throughout the United States, to enforce all laws which are now or may hereafter be enacted for the protection of animals, and to secure, by lawful means, the arrest and conviction of all persons violating such laws." (Id.)
In 1867 New York established the first significant anti-cruelty law in the United States. (N.Y. Rev. Stat. secs. 375.2 - 375.9 (1867).) For the first time, a person who "needlessly mutilated, or killed ... any living creature" could be found guilty of a misdemeanor. The law also prohibited cock fighting, bull baiting, dog fighting, impounding animals without giving sufficient food and water, carrying animals in a cruel manner, abandoning infirm animals, and similar acts.
Section 8 of the 1867 New York Anti-Cruelty Law gave ASPCA agents the power to arrest offenders, and entitled the ASPCA to keep all fines collected under the Act. At that time, the ASPCA was only one year old. "This delegation of state criminal authority to a private organization was, and is, truly extraordinary." (David Favre and Vivien Tsang, "The Development of Anti-Cruelty Laws During the 1800s," quoted from David Favre and Peter L. Borchelt, Animal Law and Dog Behavior (Lawyers & Judges Pub. Co., 1999), p. 261.)
Henry Bergh himself was also appointed a prosecutor in New York so that he could present evidence and argue for the conviction of violaters. (Coleman, supra, p. 48.) To this day, many states give similar authority to animal control officers who, in many cases, are humane society employees. (See below and, for an example of the authority of a "dog warden" to initiate a criminal case, see sec. 502(a) of the Dog Law [3 P. S. secs. 459 et seq.]: "Any person who has been attacked by one or more dogs, or anyone on behalf of such person, a person whose domestic animal has been killed or injured without provocation, the State dog warden or the local police officer may file a complaint before a district justice, charging the owner or keeper of such a dog with harboring a dangerous dog.")
From the beginning, therefore, humane societies were appointed to enforce the criminal law as it pertained to animals, and given the power to arrest violators.