Transcript for Sen. Jeff Flake talks gun control in light of Texas shooting, why he won't run for re-election
Republican senator Jeff flake's passionate speech on the senate floor is a wake-up call for the president, politicians and the entire country. That's why I'm heart broken that you're stepping down because we need more men in office like you right now. Please welcome the great senator from my state, Jeff flake. If we had an audience like this in the senate gallery I would never leave. First of all it's wonderful to have you. Our family are friends obviously. I'm heart broken you're leave. You were never a trump supporters. Neither was I. We were the dirty never Trumper. Why are you leaving? Why not stay and fight the fight? I felt that I could not run the kind of race I would need to run to be competitive. I could not speak out as I am now and as I have been over the past several months. There is no way you can become pet TV in a Republican primary particularly in a state like Arizona if you don't agree with the president's position or condone his behavior. Trump is right when he says and tweed the reason you dropped out of the senate race is because you had a 0 chance of winning. You had an 18% approval rating. If you had a better chance of winning would you have stayed? If I could have run the kind of race I'm used to running, if I could tell the truth. You couldn't win with that? No. You've can't win a primary right now if you stand up and say this is not right this is not Normal. Especially in Arizona. Especially in Arizona and other places now. It is not Normal to have a president come out like he did on Friday and try to direct the FBI and federal agencies to go out after former political opponents. That's not Normal and we shouldn't condone it. Solemn a let me ask you. You know that. We know that. What's happening in your home state that they haven't made this -- It's not just Arizona. All over the country. It's become an us versus them. Still visceral hatred the Clintons or the Obamas that we're not them and if you say anything disparaging about the president or don't condone every behavior then you're with them. I see. It's become that way. That's really affecting our politics in negative ways. We have huge issues we've got to solve that will only be solved if both parties agree to share the credit and the political risk. Now the Republican is saying we need to do what you said. When Obama got in the first thing Mitch Mcconnell said we're going to obstruct and not work with him. Democrats are supposed to work with Republicans? This is something that has afflicted us for a while. It really started when George W. Bush won the contested election in pla fla. A lot of Democrats said he's not a legitimate president. Then when Republicans got in a position to do the same they did. It's been back and forth. Is it ever going to end? It has to. We have huge issues that the only be solved. We're arguing about tax reform right now. They'reesperately needed. The last time we did it in 1986 you know how many votes it got? 97. This is a thing we needed to do. That's what they did in the past on immigration reform and other difficult issues. Today it's how can we structure the vote to make sure the right people are opposed to it and use it to beat them in the next election. It's a losing cycle. That's what it is. We've been talking about the shooting in Texas. The man gho did this was accused of assaulting his wife and child and had a dishonorable discharge in the air force. People think we need tougher background checks how do you feel about this. With regard to mental health system we have the Nick system which is sharing information with other states. It doesn't work very well with mental health. We assumed it worked well with criminal background checks. It apparently doesn't. What he was convicted of, should have shown up. Apparently it didn't. Apparently he lied on the form as well. If there were some universal system maybe it doesn't compromise the state's right to vote on their own. There has to be some similar bio Nick connective -- What we know in the past and the reason we introduced the legislation with mental health issues it doesn't always go. It needs to be adjudicated so if a court says you have mental health issues that should be something that shows up in every state. It doesn't right now, not perfectly. You have an a rating with the NRA. Now that you're not running again how do you feel about speaking the truth about the NRA? He may be speaking his truth. 75% or more of the NRA members believe there should be more background checks and control over this ar-15s. How do you feel now? I'm a member too. I grew up on a ranch on a farm. We used rifles. Not the kind they use now. No. I don't have any assault weapons. I have supported things the NRA has been opposed to. The no fly, no buy. If you are on the no fly list you shouldn't buy a weapon. I support that. With the most recent shooting in Las Vegas, the big shooting there with the bump stocks, there's no reason to have a device that makes a semi-automatic weapon act like an automatic weapon. Why do you ever need a semi-automatic weapon? Like what, a civilian why? Hunters use them. That's not fair to the animal. It's not. I would not want a ban on semi-automatic weapons. There is for good reason and most people accept it and even the NRA accepts you shouldn't be able to buy a fully automatic weapon. So you shouldn't be able to have a device that makes a semi-automatic to look like -- It doesn't make sense to me. Semi-automatic can shoot 20 shots and the automatic can shoot 50 shots. What's the difference you'll still kill 20 people? Let me jump it. I have to ask a question about the Mueller investigation. I can't ask. Senator you're a great man. I'm sorry to see you go.
This transcript has been automatically generated and may not be 100% accurate.