N.J. Stat. Ann. § 40:37-147

It shall be lawful to be present at and take part in, in county parks owned, maintained and operated by counties under authority of sections 40:37-96 to 40:37-174 of this Title, on any day in the week, any law to the contrary notwithstanding, sports, plays, games, recreations, concerts and amusements, to the extent and in such manner as the county park commission having control of the parks, shall designate; and such commission may make all necessary rules and regulations controlling and governing said sports, plays, games, recreations, concerts and amusements, and prohibiting them in such parks or parts of parks in which said board of park commissioners may deem it unwise to permit the same.