Nearly double the number of people were arrested for marijuana possession in a year in New Jersey compared to 20 years ago, according to the latest figures available.

marijuana plants (AP Photo/Jim Mone)

The change runs counter to the nationwide trend as public acceptance of marijuana use grows in the United States, leading generally to a decline in arrests.

Udi Ofer, executive director of New Jersey' ACLU chapter, said he's especially concerned by the numbers because studies show African-Americans are charged with simple possession three times as much as whites despite both groups having the same usage rates for the drug.

New Jersey's 24,765 arrests for possession of small amounts of marijuana in 2013 was the state's highest number in 20 years, nearly doubling the amount in 1993 when the population was 12 percent less, The Philadelphia Inquirer reported.

Simple possession is considered less than 50 grams, or about 1 3/4 ounces.

As legislators debate whether to legalize and regulate the drug, Gov. Chris Christie has vowed to veto any bill that would legalize recreational marijuana use.

The spike in possession arrests can be attributed to Christie's "incredibly harsh tone on marijuana use," Ofer said.

"Christie is the most vocal marijuana prohibitionist in America right now ... His rhetoric obviously hasn't been lost on the police captains of New Jersey," said Chris Goldstein, board member of PhillyNORML, a Philadelphia-based marijuana advocacy group.

A spokesman for Christie called any link between the governor's stance on marijuana and the number of arrests in New Jersey a "harebrained theory."

Bills seeking to legalize or decriminalize the drug are pending in the New Jersey state legislature.

(Copyright 2015 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)