Murphy's comments come as legislators continue to debate how to prevent shooting massacres similar to the one at Sandy Hook Elementary School in Newtown, Conn., that resulted in 27 dead, including 20 children.
Instead, LaPierre argued that posting armed guards in schools is the best way to stop a repeat of the Sandy Hook shooting. LaPierre has also criticized an assault weapons ban.
In his State of the Union address on Tuesday, President Obama urged Congress to pass universal background check legislation for gun purchasers. Obama also argued there should be a new federal assault weapons ban.
Murphy added that while he supports both an assault weapons ban and universal background checks, the ban on assault weapons is unlikely to become law.
"An assault weapons ban is going to be hard to pass," Murphy said in response to a caller arguing for an assault weapons ban.
"I support it and I'm going to push very hard to pass it, but if you talk to a lot of the families in Newtown, Conn. — and as the representative of that state I have spent over the last two months a lot of time with those families — many of them agree with you that the most important thing we can do is get these high capacity magazines off the street."