The National Rifle Association in the United States predicts that any attempt to introduce new gun laws will fail because most Americans will not support them.
The NRA said on Sunday the last time a ban on assault weapons and high capacity magazines was in place, the Columbine High School shooting still occurred.
Executive vice-president Wayne LaPierre repeated the NRA's call to place an armed guard in every school and argued that prosecuting criminals and fixing the mental health system, rather than gun control, were the solutions to America's mass shooting epidemic.
Twenty children at Sandy Hook Elementary School in Newtown, Connecticut, and six adults were killed on 14 December by Adam Lanza, 20, who shot his mother earlier.
AAP reports the tragedy has reopened a national debate on gun laws in the United States.
President Barack Obama said he would support a new bill to ban assault rifles and put Vice-President Joe Biden in charge of a panel looking at a wide range of other measures, from school security to mental health.
Democratic Senator Diane Feinstein has pledged to table a bill on 3 that would ban at least 100 military-style semi-automatic assault weapons, and would curb the transfer, importation and the possession of such arms.
"I think that is a phony piece of legislation, and I do not believe it will pass for this reason," Mr LaPierre told Meet the Press on NBC. "It is all built on lies that have been found out."
"We don't think it works and we're not going to support it," he said. "A gun is a tool, the problem is the criminal."
The NRA points to the fact that the 1999 shooting at , when 12 students and a teacher at Columbine High School in 1999, were shot and killed by two senior students - despite similar legislation being in force at the time.
"I don't think it will (work). I keep saying it, and you just won't accept it: it's not going to work, it hasn't worked. Dianne Feinstein had her (previous) ban and Columbine occurred," Mr LaPierre said.
On Sunday he defended gun owners' rights, which he portrayed as being imperiled by rich folk in cities, elite politicians and a hysterical media.
"The average guy in the country values his freedom, doesn't believe the fact that he can own a gun is part of the problem and doesn't like the media and all these high-profile politicians blaming him," he said.
"If it's crazy to call for putting police and armed security in our schools, then call me crazy," he added. "If I'm a mum or a dad and I'm dropping my child off at school, I feel a whole lot safer."