In January, Border Patrol agents walked up to a ramshackle old building on the outskirts of a small town in Arizona's Sonoran Desert. They found three men.
Two were Central Americans who had crossed the border illegally. The third was an American — a university lecturer and humanitarian activist named Scott Warren.
Warren was arrested and ultimately charged with two federal criminal counts of harboring illegal migrants and one count of conspiracy to harbor and transport them. Warren has pleaded not guilty.
Warren's arrest briefly made headlines amid the partisan tug of war over the administration's immigration policy before fading into the background.
But his legal team's decision to stake out part of his defense on religious liberty grounds has made the case a clash between two of Attorney General Jeff Sessions' top priorities: cracking down on illegal immigration and defending religious liberty.
A law written to shield faith
One aspect of Warren's defense is based on the Religious Freedom Restoration Act, also known as RFRA. At root, Warren is saying that his faith compels him to offer assistance to people in dire need, including immigrants.
Congress passed RFRA in 1993 with an eye toward protecting the exercise of religious beliefs, particularly of religious minorities, by providing narrow exceptions to neutral laws that apply to everyone.
The law would allow, for example, a religious group to use an otherwise illegal drug, such as peyote, in religious observances. In recent years, Christian evangelical groups have used the law to advance their causes.
In one prominent case, Hobby Lobby, a for-profit chain of arts and crafts stores, opposed — on religious grounds — providing its employees with health insurance that includes contraceptive services, as required under the Affordable Care Act. The Supreme Court ruled in Hobby Lobby's favor.
Warren's lawyer declined to make him available to talk with NPR for this report. But Warren's parents and others familiar with his work spoke about the case.
Sessions and religious freedom
As attorney general, Sessions has taken up the banner of religious liberty for the Trump administration.
Last year, Sessions issued a memo with guidance on protections for religious liberty in federal law.
And he called religious liberty America's "first freedom" in a July speech and vowed to aggressively protect it. He also announced the creation of a task force to help the Justice Department accomplish that goal.
One of its jobs, he said, would be to ensure that the cases that DOJ attorneys bring and defend — and the arguments they make in court — are in line with federal protections for religious freedom.
"That includes making sure that our employees know their duties to accommodate people of faith," Sessions told the crowd. "As the people in this room know, you have to practice what you preach."
But some critics say the Justice Department is failing to do just that. Instead, they say the DOJ is selectively supporting religious liberty.
"There's a public face of this government, which is very protective of religious liberty, and then the real work they're doing is only protecting the religious liberty rights of those who are religious conservatives, not of religious progressives," said Katherine Franke, director of the Public Rights/Private Conscience Project at Columbia Law School.
Franke was one of several law professors who filed a friend of the court brief in Warren's case to help explain the statute.
The American Civil Liberties Union also has accused the Trump administration of uneven support for religious freedom.
"The Trump administration's view of religious liberty is both selective and distorted," said Daniel Mach, director of the ACLU's program on freedom of religion and belief.
"It supports an unfounded, unprecedented religious license to discriminate; and at the same, the administration is indifferent or outright hostile to faiths and religious individuals with which it disagrees."
The Justice Department declined to respond on the record to those allegations.
Many conservative groups and faith leaders have lauded the Trump administration for its efforts to protect religious freedom and people of faith.
One of the most prominent examples of that support was the Justice Department's decision to file a brief in support of a Colorado baker who refused to make a wedding cake for a same-sex couple.
United States v. Warren
Warren, who worked as an instructor at Arizona State University, volunteered with a humanitarian organization called No More Deaths. The group aims to save lives in the U.S.-Mexico borderlands, where people frequently die as they try to cross the desert during the journey north.
To that end, volunteers for the group hike into the scrubland and leave food, water and other supplies. They also provide emergency first aid to people they find in distress.
No More Deaths and other humanitarian groups use a private residence they call "the barn" on the outskirts of the small town of Ajo, Arizona, as a base of operations.
That's where Warren discovered Kristian Perez-Villanueva and Jose Arnaldo Sacaria-Goday in January, according to court papers.
Warren found the two men hiding in the barn's bathroom, the government says. He gave them food, water and clothes, and he allowed them to stay for three days.
On Jan. 17, Border Patrol agents and local law enforcement officers conducting surveillance on the barn saw Warren talking with "two subjects that matched a description given of two lost illegal aliens," court papers say.
The agents approached the barn on foot and spoke with Warren, who told them to leave, prosecutors said.
The agents then conducted a "knock and talk," during which they identified Perez-Villanueva and Sacaria-Goday and determined they were in the country illegally. Warren was arrested, while the two undocumented men were detained as material witnesses, deposed and then deported.
The U.S. Attorney's Office for the District of Arizona declined to comment on Warren's case.
It's unclear whether national political dynamics played any role. But the group No More Deaths believes it is connected to the Trump administration's broader crackdown on illegal immigration.
"What we see under DOJ now is that they're going after the activists," said No More Deaths volunteer Catherine Gaffney. "But unfortunately when you go after activists, they're going to raise their voices and fight back and not be deterred."
Gaffney also raised questions about the timing of Warren's arrest.
She said it came hours after No More Deaths released a report that accused Border Patrol agents of slashing water jugs that the group had left in the desert. The report included videos of Border Patrol agents destroying plastic water containers.
"So we see a clear pattern of political attack here and of weaponizing these immigration statutes to go after the activists," Gaffney said.
Warren and RFRA
Warren, whom neighbors called an active citizen within the town of Ajo, filed a motion earlier this year to have two of the charges dismissed on RFRA grounds.
Under the law, he has to show three things to make his case: that his beliefs are religious in nature; that they are sincerely held; and that they are substantially burdened by a law that applies to everyone.
If he can do that, the burden of proof then shifts to the government.
Prosecutors have to show that the government has a powerful reason to apply the law in Warren's specific case. They also have to show that the government is using the least restrictive way possible to accomplish that.
At a court hearing in May, Warren testified about his beliefs. He described a life force that permeates all things — animate and inanimate. And his faith, he said, compels him to act when someone is in need.
"For me, we most definitely do unto others as we would want to have done unto us," he told the court.
The government opposed the motion, saying the prosecution does not substantially burden Warren's beliefs. DOJ lawyers said Warren "is not required by his beliefs to aid in the evasion of law enforcement. Nor were the people associated with these charges 'in distress.' "
The district judge presiding over the case denied Warren's motion to dismiss it. But the judge left the door open to Warren to try again when he's scheduled to go to trial in November.