JUDY WOODRUFF: And to our two-part look at immigration.
On the U.S. Supreme Court docket Wednesday is a tough new law in Arizona.
NewsHour correspondent Tom Bearden traveled there recently and sets the scene for tomorrow's arguments.
TOM BEARDEN: Daniel Bell's family has raised cattle on this land along Arizona's southern border since the 1930s. But in the past few years, he's had to repair the simple barbed-wire fence that separates the U.S. from Mexico more and more often, because the steady stream of people entering the country illegally are always cutting it.
DANIEL BELL, Arizona: So this is a common occurrence every day that we deal with on the ranch.
TOM BEARDEN: Do you ever get mad about this?
DANIEL BELL: It gets frustrating. It definitely does.
TOM BEARDEN: Bell says the ranch has become a much more dangerous place, too.
Do you fear for your life out here?
DANIEL BELL: Yes, when we're out in places like this, where we don't have communications, and you're always thinking, what am I going to do if something happens?
TOM BEARDEN: Have you ever come across armed people coming across the border?
DANIEL BELL: Yes, I have, on several occasions. And the most recent one was actually when we were building this fence. We were hauling material in with a mule and we came around on a trail that's used by smugglers, and ran right into a group of about 10 people. The first guy was carrying a long arm, an AK-47.
TOM BEARDEN: An assault rifle?
DANIEL BELL: An assault rifle, yes.
TOM BEARDEN: That massive fence down there is one of the reasons why so many illegal migrants are crossing over the border ranch lands. When the federal government put it up, it forced them to move out into the desert. And what happened after that is one of the reasons why the state legislature passed the law that the Supreme Court is now reviewing.
Rancher Robert Krentz was murdered on his land in March 2010. Some authorities suspect he was killed by an illegal immigrant, but the case remains unsolved.
MAN: I'm tired of those folks who simply advocate we don't enforce our laws. I'm tired of those folks who simply ignore the damage to America and the deaths of folks like Rob Krentz.
TOM BEARDEN: Former state Senate President Russell Pearce authored the bill.
RUSSELL PEARCE (R), former Arizona state senator: What's coming across that border today are gangbangers, drug smugglers, human smugglers, child molesters, bad guys. They live in fear of their lives. Their waterlines are cut. Their animals are slaughtered. Their dogs' throats are cut. Their fences are torn down. They're threatened. Some of them have their windows and doors boarded. They pray for daylight. If they hear noises, they don't dare come outside.
TOM BEARDEN: Gov. Jan Brewer signed the bill into law two years ago. It's often referred to as Senate Bill 1070.
The law makes it a state crime to be in the country illegally or to seek work while here. It requires local law enforcement to verify the citizenship of anyone they suspect might be undocumented. And it gives police the authority to make warrantless arrests in such situations.
Those key sections were blocked by a federal judge after the Justice Department sued, arguing that for each state to set its own immigration policy would wholly subvert Congress' goal, a single national approach. And that's the question before the Supreme Court now, whether federal immigration law preempts the state of Arizona from making its own rules.
That argument doesn't sit well with Phoenix resident Connie Liston, a supporter of the law.
CONNIE LISTON, Phoenix, Ariz.: I wouldn't object to someone asking me if I am a U.S. citizen. When I come back from Mexico every trip, they ask me that question. I don't think it should offend anyone.
TOM BEARDEN: About two-thirds of Arizonans supported Senate Bill 1070 when it was first passed, and polls show the same numbers continue to support it today.
But it's a complicated picture, says Bruce Merrill, founding director of the Survey Research Center at Arizona State university.
BRUCE MERRILL, Arizona State University: There's two very strong components. One is the border itself; 75 percent to 80 percent of the people in Arizona really want more done to keep people from coming across the border.
But the issue is, what do you do with the families that have been here for 25, 30 years? About a third of them have children that are United States citizens, and should they be allowed to stay here and be given a path to citizenship? Sixty-five percent of the people in Arizona feel that these families should be given an opportunity to gain citizenship.
TOM BEARDEN: Families, perhaps, like Sandra's, who spoke to us on the condition we use only her first name.
You came across the border without papers?
SANDRA, illegal immigrant: Si.
TOM BEARDEN: Sandra entered the U.S. illegally 18 years ago with her four children, seeking medical care for a son with special needs.
SANDRA (through translator): Not all the illegals are the same. It depends on why we're here. Many of us come here to work, to study.
TOM BEARDEN: Sandra says SB-1070 terrified undocumented workers.
You said you lived in fear. Tell me about that.
SANDRA (through translator): It's a feeling that's always there. It's a fear that's always there. In the morning, when we go to work, we always say goodbye, thinking that maybe we won't see each other. Always, every single day, we leave with that thought, that maybe we won't be back home.
PETRA FALCON, Promise Arizona: SB-1070 has created ongoing human tragedies.
TOM BEARDEN: Petra Falcon runs an immigrant rights group that opposes the law, and works with families like Sandra's every day.
PETRA FALCON: What is happening since SB-1070 is that families continue to be stopped on the road, and that leads to incarceration. That leads to separation of families. That leads to deportation. People cannot find work because it's assumed that they don't have papers.
TOM BEARDEN: Arizona's undocumented population has dropped sharply in recent years. It's unclear how much of that is due to the law, the downturn in the economy, or some combination. Not everyone is sympathetic.
JOE ARPAIO, Maricopa County, Ariz., sheriff: The last I heard, coming into the United States happens to be illegal.
TOM BEARDEN: Joe Arpaio is the sheriff of Maricopa County. He holds prisoners detained on immigration charges in tents, exposed to the extremes of Arizona's weather.
ENRIQUE PENA, prisoner (through translator): In a little while, the heat is going to average 110 degrees, and the heat accumulates. At night, it's a hellish cold.
TOM BEARDEN: Arpaio is known for his get-tough attitude toward crime, including his color of choice for prisoners.
JOE ARPAIO: The pink underwear which you can see, it matches the sheets. But you know what? They don't like it, don't come to jail. Very simple.
TOM BEARDEN: The 79-year-old sheriff says he'll continue to enforce all of the provisions of Senate Bill 1070, no matter what the Supreme Court decides.
JOE ARPAIO: I'm still going to do what I'm doing. I'm still going to arrest illegal aliens coming into this country. I'm still going to raid businesses. I'm still going to crack down on crime-suppression operations.
TOM BEARDEN: Arpaio is currently under investigation by the Justice Department for alleged racial profiling. That's something President Obama has said is a potential risk when it comes to enforcing SB-1070.
PRESIDENT BARACK OBAMA: Now, suddenly, if you don't have your papers and you took your kid out to get ice cream, you're going to be harassed. That's something that could potentially happen.
TOM BEARDEN: The sheriff of Santa Cruz County, Tony Estrada, shares that concern.
TONY ESTRADA, Santa Cruz County, Ariz., sheriff: I don't think there's any question that there will be racial profiling, because obviously the bill is tailored to looking at a particular group of people. You're looking upon Hispanics. And you'll be looking at a lot of people that come into this community. And they're all going to be suspects in one way or another.
They asked me, will you enforce SB-1070 if it becomes law? My response is, I will. I have a responsibility to do that. But it's going to be at the bottom of my priorities, because I cannot afford it.
TOM BEARDEN: The administration touts the fact that illegal crossings have decreased on President Obama's watch. Border Patrol agents apprehended some 340,000 migrants in 2011, down from a peak of over a million in 2005.
But Russell Pearce, who lost his state Senate seat in a recall election last November after taking criticism as the author of SB-1070, says that's not good enough.
RUSSELL PEARCE: Crossings are down for a lot of reasons at the border. One is, Arizona has gotten better. We do have more Border Patrol there. But the violence is up. And what's going on across America itself, it's a national crisis.
The administration -- and I will tell you, there's a lot of misinformation about what they have done. They have done very little.
TOM BEARDEN: Back on the front line of this issue, Dan Bell and his ranch hands spend time and money cleaning up the debris left behind by the steady stream of border crossers.
DANIEL BELL: There's a blanket, water bottles, just all kinds of things. And each little canyon we go up, you'll find trash just everywhere scattered out.
TOM BEARDEN: Even so, Bell isn't convinced that SB-1070 is the answer.
DANIEL BELL: Well, I think if you're looking at the metropolitan areas, where somebody gets pulled over and can't produce a license, that's where SB-1070 would kick in. But right here on the border, I don't see where it would do us any good.
TOM BEARDEN: Justices are expected to issue their decision by late June.
JUDY WOODRUFF: Online, you can see an impromptu encounter between Sheriff Arpaio and one of the inmates in his jail.
In Washington today, Sen. Charles Schumer said Democrats will introduce legislation to block Arizona's law if the Supreme Court upholds it. Meanwhile, five states have passed laws modeled after Arizona's. Federal judges have blocked all of them from being fully implemented, pending the high court's ruling.
Attorneys general in 11 more states have filed a friend-of-the-court brief against Arizona's law, siding with the Obama administration.
We'll have full coverage of the Supreme Court arguments tomorrow.