Enacted to make it harder for Mexican drug cartels to obtain military style weapons from America, the law requires gun merchants in Arizona, California, New Mexico and Texas to report within five days if someone buys more than one semi-automatic weapon like an Ak-47.
The lawsuit asserts the administration exceeded its powers, passing the measure without congressional approval.
“N.R.A. has always viewed this as a blatant attempt by the Obama administration to pursue their gun-control agenda through back-door rule making, and the N.R.A. will fight them every step of the way,” said Wayne LaPierre, the executive vice president of the gun-rights group.