Back-to-back mass shootings in Georgia and Colorado underscore how loopholes and weak restrictions in gun laws enabled both suspects to get quick access to their weapons of choice in attacks that left 18 people dead.

The two shootings in March have thrust the issue of gun violence back into the national spotlight – and with it, calls for changes in gun requirements.

While the shootings are unrelated and on different ends of the country, they both exposed issues within current gun laws. Namely, they show that nuances in laws – or no laws at all – allow certain guns to skirt state and federal statutes.

The suspect who police say opened fire and killed eight at three spas in Georgia – an attack that shook the Asian-American community – bought a handgun just hours before the massacre. Georgia has no state law requiring a firearm waiting period, a requirement in 10 states and the District of Columbia that aims to save lives by delaying a potential killer from acting on impulse.

Six days after the Georgia assault, police say a man described by family members as mentally ill attacked a Colorado grocery store and killed 10, including an officer. Police say in the days before the attack, the Colorado suspect purchased a Ruger AR-556 pistol that experts say largely mirrors a short-barrel rifle.

Federal law allows the Ruger to be categorized as a pistol, granting the suspect easy access to the weapon without the extensive restrictions placed on short-barrel rifles.