Transcript for 'This Week': Marijuana Legalization
And now with our expert with us, and Allison from Washington state's aclu, Pierre Thomas and ricar ricardo, the marijuana editor of the Denver post. No paper has had that before. You surprised me a little bit here, you started out skeptical, but you've evolved. I'm a parent of two teenage boys, I'm a pediatrician. I'm concerned about the impact on the developing brain from frequent use. I went in thinking there's no way it should be legal. The more I got into the story, the more I was convinced bit arguments around the comparison between alcohol and its dangers and marijuana. It's just not rational that adults don't have the choice of using marijuana, but they do for alcohol. Marijuana is less likely to be addictive, cause car accidents and birth defects. Less likely to cause domestic violence. How do you rationally say that it's okay to drink alcohol with that profile, but it's not okay to occasionally use marijuana? How do you do that, Pierre? I spent time doing research and talking to law enforcement officials, one thing they point out is this is not your daddy's marijuana. The marijuana today is three times more powerful with the thc, the active ingredient. They're concerned about the effect on younger people. That's one of the things they are concerned about. And they say you have to look at how is the legal system going to adjust to accommodate this. You saw with the state trooper. There's no way to test for it on the highway. And I want to bring that to ricardo. You're on the ground with the marijuana beat in Colorado. And it is unprecedented. I have to ask you the first question you always get, do you use it? I do. I use it both medically and recreationally. Okay. And then what are you seeing on the ground? I was most struck by one of your observations. You can ell the difference? That's if Denver and Boulder? You can. If you went back a couple years in the metro area and took a big whiff in downtown Denver, downtown Boulder, it would have been your average city. At a broncos game, you can smell the difference. We were at the Justin Timberlake concert, and you could smell it there. Of course, it's been ever-present at concerts for decades. What's the biggest challenge? It comes down to keeping it out of kid's hands. But also keeping it from crossing state lines. When that justice department memo came out saying Colorado, Washington, go for it but we're watching you. We have to pay attention to those bits and pieces that are very important. You are part of the campaign in Washington state to legalize it. And we are seeing it in other states as well. Oregon, Alaska, California, they don't know when. And nationwide, the conversation has changed from does it make sense for us to continue treating this like a criminal matter, to how can we do this in a responsible way, where we're not only focusing on keeping it out of kid's hands, but also providing kids proactive information to make better choices. The president made the powerful argument, tried to clarify, it's just not fair that you're a young african-american kid, you're going to get a far harsher sentence than someone else. But doesn't that leave to the argument, why not just stop at decriminalization, why not legalize it? I think the concern with stopping with decriminalizing, we have to address the black market. Kids are going to get marijuana that's three-times as strong with thc. That's outside of regulation. We need regulation, licensing and standards. And the other counterargument, and pot may be no worse than alcohol, but once you get a whole lot of money and marketing behind it, we have seen it with cigarettes and alcohol. The kids will use it earlier and earlier, and potentially get hooked. And I think that is one area there has to be focus on regulation. And look closely at what happens in Colorado and Washington state and learn from that experience. I do worry about kids using this. And we have to be clear in this that it's not a signal saying it's okay for kids to smoke pot. But I know in the community we live in, kids are smoking pot without this. And hopefully bringing it away from the black market and out in the open, we're able to get those messages through. Is that signal being sent in Colorado? Do you feel that? It's definitely being sent. And rich makes a good point, this is in middle schools and high schools. It's everywhere. But the education process is very serious. I know the state has been making in-roads in high schools and going out and having conversations. And we take our job responsibly in terms of educating the public too. This is a strong product. You know, start with -- You write about that. I do. Yeah, yeah. We have written multiple times about the strength of it and good amounts. It's good to start if you're new with 5 milligrams of an edible. It's a solid way of measuring the amount of pot that you're about to ingest. George, one of the things that struck me is when you start to look at the marijuana, Americans have had a love afire with marijuana. Look at the black market. They are trucking it into the country my the hundreds of tons. I went to a secret location where the government disposes of it, and it's by the forklift. It's incredible. It's tough to keep it out of the hands of kids. It is. Right now it's hard to keep alcohol out of the hands of kids and marijuana, and we need to do a better job around that. A lot of that comes down to parenting. Education in school's one thing, but it comes down to what are you saying at home and what examples are you setting? But in doesn't change that. The fact that it's illegal now, kids are using this, it's rampant. Saying it's legal for adults to use that is a rational approach. That is all we have time for. I wish we had more time. I want you to come back. Thank you very much.
This transcript has been automatically generated and may not be 100% accurate.