http://www.state.nj.us/sci/pdf/spca.pdf
Excerpt:
ARREST POWERS: The legislative provision governing arrests for violations of the animal cruelty laws is contained in N.J.S.A. 4:22-44. It empowers only the state society and not the county societies. Arrests may be made with a warrant or without a warrant when the violation occurs in the individual's presence. Since the provision was first enacted in 1880, the power to arrest has been conferred not only upon the NJ SPCA's officers and agents, but also upon its members. However, nowhere in the statutes governing the societies is the term 'member' defined. Therefore, it includes dues-paying members and those members of the Board of Directors who are not agents or officers. These individuals receive no law enforcement training.
http://www.state.nj.us/sci/pdf/spca.pdf
Excerpt:
POWER TO CARRY WEAPONS: Perhaps the most disturbing area of unbridled authority bestowed upon SPCAs is the ability of their officers to carry firearms without being subject to governmental oversight or to most of the stringent requirements governing legitimate law enforcement officers. While some SPCAs do not allow their officers to carry weapons or do not use the designation 'officer' in order to eliminate the firearms issue, the officers of nine SPCAs are armed. Both county and state SPCA officers are exempt under NJSA 2C: 39-6c(7), which empowers SPCA officers to carry weapons in the actual performance of their official duties.