New York state's 2013 gun law includes a ban on the sale of so-called military-style assault weapons like this AR-15 rifle. Charles Krupa/AP hide caption

itoggle caption Charles Krupa/AP

Elizabeth Shirley's lawsuit, which resulted in a settlement for $132,000, could send a message to gun dealers across the country. But for now, the precedent will only have weight in Kansas. Ethan Miller/Getty Images hide caption

itoggle caption Ethan Miller/Getty Images

Rick Ector trains new gun owners at a range just outside of Detroit. He supports more African-Americans getting permits to carry concealed weapons. Martin Kaste/NPR hide caption

itoggle caption Martin Kaste/NPR

Colorado educators take part in a concealed carry course in Englewood, Colo., on Nov. 8. The course is open to all state school employees. Participants who complete the training are eligible to apply for a permit to carry a handgun. MATTHEW STAVER/Landov hide caption

itoggle caption MATTHEW STAVER/Landov

In 2010, Omar Thornton killed eight colleagues in Manchester, Conn., before killing himself. Private employers used to create their own rules about guns on their property. But over the past five years, many states have adopted laws that allow employees to keep firearms in their vehicles at work. Douglas Healey/Getty Images hide caption

itoggle caption Douglas Healey/Getty Images

Firearms for sale at a gun show in Annapolis, Md., on April 14. Andrew Harnik /The Washington Times /Landov hide caption

itoggle caption Andrew Harnik /The Washington Times /Landov

This AR-15 style weapon was on display in March at the 7th annual Border Security Expo in Phoenix, Ariz. It's among the type of weapons that advocates of new gun laws want to see banned. Joshua Lott /Reuters /Landov hide caption

itoggle caption Joshua Lott /Reuters /Landov

A Bushmaster rifle, similar to the type used by Adam Lanza during the shooting at Sandy Hook Elementary School, and some ammunition magazines. The sale and possession of this type of weapon, and high-capacity magazines, will be severely restricted in Connecticut under new legislation. Michelle McLoughlin /Reuters /Landov hide caption

itoggle caption Michelle McLoughlin /Reuters /Landov