A man holds a child at gunpoint after shooting and killing a school bus driver which was our lead story tonight. And another man, walks into a Phoenix office building and opens fire, hitting three killing one. Those are just two headlines from today, there've been many other recently, some far worse, of course. "Keep them honest" though, how big role if any does easy access to firearms play in violent crime like this. That's a question, crucially how do we really know what the true facts are, you know, our both sides building their cases on, on shaky factual ground. Today in testimony before the senate judiciary committee, former Congresswoman Gabby Giffords who survived the Tucson massacre spoke of the need for action.

"Thank you for inviting me here today, this is an important conversation for our children, for our communities, for Democrats and Republicans, speaking is difficult, but I need to say something important. Violent is a big problem, too many children are dying, to many children, we must do something. It will be hard, but the time is now. You must act, be bold, be courageous, Americans are counting on you. Thank you."

Well, she spoke from handwrite note which were posted on the facebook page, the gun reform group, that she and her husband, former astronaut, Mark Kelly, founded. He also testified along with the National Rifle Association's Wayne LaPierre and others, commander Kelly at one point answering Mr.LaPierre's claim that background check don't need to be made universal.

"My wife would not be sitting in this seat, she would not have been sitting here today. If we had stronger background checks."

On the NRA position, though, and it's shared by many people that criminals would still be able to get and use firearms tha banning high capacity magazines would similarly not work, nor would with reinstating the ban on semiautomatic weapons. Such as the one used in Newtown, Aurora and elsewhere. Now there is just one problem, both sides on the gun debate, use the assault weapons ban, which was in effect from 1994 to 2004 to make there case. Listen.

"Independent studies, including one from the Clinton justice department, prove that it had no impact in lowering crime."

"The department of justice report assault weapons as a percentage of gun, of gun traces, which shows the 70% decline."

"While arm security works, gun bans do not."

"I've been as law enforcement for nearly 35 years, I've seen an explosion of fire power since the assault weapons ban expired, victims are being riddled with the mutiple gunshots."

"To reenact a law that according to the Department of justice did absolutely nothing to reduce gun violence."

"The 1994 assault weapon ban did not stop columbine, the justice department found the ban ineffective."

You might hear all those sides and say to yourself, all both sides can not be right. The problem is there is really no clear cut way of telling who is, not just because each side accuses the other of cherry picking the data. The real problem is that there simply not enough good research to draw solid conclusions. Take a look at where the nonpartisan congressional research services, concluded in a November report on the existing body of knowledge, and they quote, "none of the existing sources of statistics provide either comprehensive, timely or accurate data with which to assess definitively whether there is a cause of connection between firearms and violent  And a big reason for that scarcity of good research, well, Congress under pressure from the gun lobby doesn't pay for it. Take a look from 1993 through 1996, Congress allocated about $2.5 million dollar annually, so the Centers for Disease Control, the CDC, could study gun violence. But since 1996, the money has dried up, averaging just $100,000 a year over the last three years and a budget of nearly $6 billion. Now, having said all that, the lack of definitive research has not stopped policy makers and community members from doing what they can with what they've got in the struggle against gun violence and learning as they go. Few know that better than long time New York City police commissioner Ray Kelly who joins me now.