President Barack Obama on Wednesday proposed a package of
measures intended to reduce gun violence in the wake of the
Newtown school massacre last month. Some of the steps have been
tried before and others are expansions of laws and policies
already in place. Some face high hurdles in Congress. Will they
work? Here's a look at some of the key measures: Ban on assault
weapons The Federal Assault Weapons ban, a provision of anti-
crime legislation President Bill Clinton signed into law in
1994, outlawed military style semiautomatic weapons that fire
one round per trigger pull and automatically eject the shell
casing and reload the chamber. In addition to these weapons, the
ban also limited semiautomatic rifles, semiautomatic pistols and
semiautomatic shotguns that can accept a detachable magazine and
have at least two military style features. Congress allowed the
prohibition to expire in 2004. Sen. Dianne Feinstein said in
December that she would introduce a bill to ban assault weapons.
Did it work?: Two studies