ABC This Week interviews during 2015: on Immigration

Donald Trump: Need to keep database of Muslim refugees

TRUMP: No, not at all. I want a database for the refugees that come into the country. We have no idea who these people are. When the Syrian refugees are going to start pouring into this country, we don't know if they're ISIS, we don't know if it's a Trojan horse.

And I definitely want a database and other checks and balances. We want to go with watchlists.

Q: Just for the record, though, the statistics do show the majority of the refugees coming in are women and children.

Ben Carson: Guest worker program; no citizenship for illegals

CARSON: If they have a pristine record, I support giving them an opportunity to register as guest workers so they're not living subterranean. They have to pay a back tax penalty and they have to pay their taxes going forward, they don't get to vote and they aren't citizens. But my long-term plan would be for us to allow American businesses to go over there, develop the acreage, create jobs and teach those people the agri business, while also making profit. If we do that in Central America and South America and help them to be able to improve their own standard of living there, they won't need to come here.

Donald Trump: Syrian refugee crisis partly our fault; but don't take any

TRUMP: I saw the migration and it seems like so many men. There aren't that many women or childr It looked like mostly men and they looked like strong men.

Q: Half the refugees are children.

TRUMP: We don't know where they're coming from. We don't know who they are. They could be ISIS. I understand the whole thing with migration. It's a horrible thing. It should have never happened in the first place. We screwed up the Middle East so badly, with breaking up Iraq. We have so destabilized the Middle East. So I said there's no way they come in. If they do come in, if I win for president, they're going out.

Q: Even the kids?

TRUMP: Look, Europe should take some probably, because you have the Gulf States, Saudi Arabia, Bahrain, Qatar--some of the richest countries and they're not taking any in.

Ben Carson: Many immigrants are criminals from Iraq, Somalia and Russia

CARSON: Well, I talked to a number of the sheriffs on the borders and they've told me what kind of people are coming over. So I'm not sure that I would trust, quite frankly, any figures coming from the government, given the fact that they are the ones who are problematic. You know, a lot of these people who are captured, it's ICE who comes along and says, "you must release these people."

Ben Carson: Taking in Middle Eastern refugees could be dangerous

CARSON: I would recognize that bringing in people from the Middle East right now carries extra danger. And we have to be extra cautious. You know, we need to tighten it up and be very careful, because we cannot put our people at risk because we're trying to be politically correct.

Donald Trump: The border wall will be well-managed and built correctly

TRUMP: I'm telling you, it's called management. You can do this and we can expedite the good immigrants to come back in. And everybody wants that. But they have to come in legally. We have to be a country of laws and borders. We have wonderful Border Patrol people, but they're not allowed to do their job. I will get the best people to build this wall and we will do it properly and we will do it humanely and get the good ones back in.

Rick Perry: I secured the border & reduced apprehensions as Texas Gov

PERRY: Well, I don't think he understands the challenge, obviously. I was the governor of Texas for 14 years. The governor of that state with the 1,200 mile Mexican border. When it became abundantly clear that the president wasn't going to deal with this immigration issue, we acted last summer. We surged our law enforcement and our National Guard there. And as a result we saw a 74 percent decrease of apprehensions in that region of the border where the real challenges were.

Scott Walker: No amnesty, but no mass deportation either

WALKER: I think for sure, we need to secure the border. I think we need to enforce the legal system. I'm not for amnesty, I'm not an advocate of the plans that have been pushed here in Washington. We've got to have a healthy balance. We're a country both of immigrants and of laws. We can't ignore the laws in this country, can't ignore the people who come in, whether it's from Mexico or Central America.

Q: But is deporting them possible?

WALKER: That's not what I'm advocating. I am saying in the end, we need to enforce the laws in the United States, and we need to find a way for people to have a legitimate legal immigration system in this country, and that does not mean amnesty.