They just missed the turn. Luis Mora, a 20-year-old student at the University of California at Berkeley, and his girlfriend were driving home from a birthday party near San Diego on their recent winter break. It was dark, and they didn’t know the road.

Just past the turn toward home, they realized they were lost, and saw blinking lights. His girlfriend pulled over. It was a Border Patrol checkpoint, about 30 miles from the Mexican border.

When the officer learned Luis Angel Mora Villota was not in the United States legally, he asked Mora to step out of the car, snapped handcuffs on him and told him he was under arrest.

It was the moment that many students from other countries, in the United States illegally, dread. It was a moment that set off a wave of activism, with students, community members, U.S. senators and other political leaders trying to help the student.

And it was a moment that symbolized one of the sharpest divides in this polarized country: Should a bright and hard-working young person be forced out? Or should the law be enforced fairly for all, to deter illegal immigration and keep our country safer?

“A lot of students are wondering how dangerous the situation is,” said Valeria Suarez, a third-year student at Berkeley, who co-chairs a student group that helps immigrants and has worked on deportation defense funds in the community. It was a shock, she said, that the person needing help this time was a classmate.

At this point, Mora said, he’s just hoping his case will show that immigration laws need to be fixed. After so many years of trying to achieve legal status, he has concluded that no matter how much effort you put in and how resourceful you are at navigating the complicated process, “at the end, at the very end, it’s just out of luck. It’s just whether the algorithm picks you.”

Mora was brought to the United States by his mother when he was a child.

He was born in Colombia, but spent most of his childhood in Ecuador. When he was 11, he and his mother, who was a doctor and a missionary, came to California, legally, to help care for family members who were sick. He didn’t know the other, perhaps more important, reason for the journey until years later.

One day, she gave him school supplies and a backpack, and told him he was going to start school that day with his cousins.

And when their six-month visa expired in 2009, they stayed.

He was too young to understand, and didn’t know until he was in high school, that they had left Ecuador because his mother had been diagnosed with breast cancer. She did not have much hope of survival, but in the United States, she knew, she would be able to get better medical care.

Mora studied hard, and had to grow up quickly; at 12, he was preparing the family’s tax returns.

And his mother, with good care, did survive. But as he finished high school, Mora and his mother believed they had little choice but to return to Ecuador. The day after his graduation, they went to church and said farewell. A friend told them about a California law that allows some undocumented students to attend public universities. When he found out he was eligible, he said, “I was excited. My mother took it as a sign that I was meant to stay.” She returned to Ecuador, and he enrolled at a community college in California.

He volunteered at church and in his community, learned English so well he began tutoring native-English speakers in writing and was honored as a student leader by the San Diego Union-Tribune in 2016.

He met his girlfriend, who works in a hospital emergency room, while doing volunteer work at a community college. As an honors student there, he was able to transfer to Berkeley to study political science this past fall.

He would like to become a U.S. diplomat, he said. “I want to help people.”

But as classes resumed Tuesday after winter break, Mora was not there.

He has been in U.S. Immigration and Customs Enforcement custody at the Otay Mesa Detention Center in San Diego, after several days in a holding cell where government-issued blankets covered their heads, making the room look, he said, like it was packed with shrouded corpses.

He has a hearing before an immigration judge Wednesday, according to Lauren Mack, a spokeswoman for U.S. Immigration and Customs Enforcement.

Prerna Lal, immigration lawyer for UC-Berkeley’s undocumented-student program, said it is extremely unusual that someone would be detained for overstaying a visa; typically, people charged in such cases are allowed to come and go to their court hearings. She said it is a sign of “the hateful political climate we are living through. Things are getting worse for immigrants. Luis is a casualty in all this.”

Mack said the immigration judge will determine bond.

Mora consulted a lawyer but did not qualify for the Deferred Action for Childhood Arrivals program, Lal said, because he arrived in 2009, two years after the cutoff for DACA. He might have qualified for the expanded DACA program that was stalled by the U.S. Supreme Court, Lal said.

Earlier this month, Berkeley Chancellor Carol Christ told the campus, “We recognize the urgency of this moment. As such, the university is currently working to ensure that the student has access to legal advice, attorney services and other resources necessary to mount what we hope will be a successful effort to end this detention.” Christ said staff members have been working with state and federal leaders, some of whom have issued statements advocating for the student’s release.

The school has an estimated 500 undocumented students, said Janet Gilmore, a Berkeley spokeswoman. Christ also said she was ensuring that people are aware of the bail fund that students started.

Within two days of learning of the bond hearing, the student group leader Suarez said, people contributed 135 letters of support to give to the judge.

The social media campaign also brought comments from people who felt Mora’s detainment was appropriate.

Mora is trying not to think about what would happen if he is sent back to Ecuador; he knows it would jeopardize the hard work he has put into his education and his community. “I believe in God, and I believe there are things you’re meant to do,” he said. “All of this overwhelming support . . . tells me that there is a nation that tells me to be strong, for myself and many other people.”

If he were to go back to Ecuador, Mora said, through tears, “I would be homeless.” His mother, now working as a missionary, would not be able to support him. He has not seen his father for many years. If forced to return, he would immediately try to find a way to legally immigrate to another country, perhaps in Europe, in hopes of continuing his education, he said.

“I know this is my home,” Mora said, as he waited anxiously for his hearing Wednesday, “despite the fact that I can’t call it my home legally yet.”

He said he hopes to finish college, to serve in the military, and work for the U.S. government one day — legally. “That has been my goal: Acquire a legal status through education, and serve this country that has given me so much.

“… In my heart,” he said, “it is home.”

His life is about to take another turn. On Wednesday, he’ll begin to see which way the road ahead leads.