The MT GOP Ebrief says that a study by the Centers for Disease Control "has concluded that the nation’s gun control laws have not reduced gun violence. The CDC panel reviewed 51 independent studies about the effectiveness of gun control legislation and in every case found that there was 'insufficient evidence to determine effectiveness.'"

Just on the surface, it's perfectly clear that "insufficient evidence" does not amount to a conclusion. Indeed, the CDC specifically warned against reaching one.

"When we say we don't know the effect of a law, we don't mean it has no effect. We mean we don't know," said Dr. Jonathan Fielding, chairman of the CDC task force. "We are calling for additional high-quality studies."

Interesting, too, that the ebrief didn't find this 1997 CDC study worth mentioning. Key conclusion: Among 26 industrialized countries, the United States has a rate of firearm-related deaths among children that is 2.7 times greater than that of the next highest country. Guns don't kill people; children do.