The U.S. is installing more rock barriers to target illegal border crossings. Will they work?

In a Jan. 27 video taken in broad daylight, a group of men are seen laying down sheets of wood over a steep ditch. A black truck then drives over the wood and into British Columbia from Washington state.

The group of five Romanian nationals, one of whom had an outstanding arrest warrant out of the U.S., were arrested, according to the Canada Border Services Agency and RCMP — the latest of dozens of illegal vehicle crossings along the world's longest undefended border.

Since 2023, 85 vehicles have illegally driven across the border near Blaine, Wash., according to Chief Patrol Agent Rosario Pete Vasquez, who says the number is growing.

It has prompted the U.S. Border Patrol to install rock barriers to act as physical markers that separate the border between B.C. and Washington state. Border security experts say the tactic makes the U.S. look like it's being tough on the border but may not deter illegal crossings.

"My perspective is that much of what we see happening along the physical barrier is a little bit of political theatre," said Laurie Trautman, director of the Border Policy Research Institute at Western Washington University.

Keith Cozine, an associate professor of homeland security at St. John's University in New York, says he believes the rock barriers are in response to the new White House administration to show that the northern border is a big threat.

Game of 'cat and mouse'

Rock barriers are not a new concept and are not unique to Washington state, according to U.S. Border Patrol. 

This week, patrol agents installed dozens of rock barriers along portions of 99th Street West in Blaine, across from Surrey, B.C.

"We are committed to safeguarding the residents of northwest Washington while ensuring the integrity of our border," Vasquez said in a statement to CBC News. 

"These measures are designed to enhance security and protect our communities from the potential dangers posed by these incidents."

The U.S.-Canada border has come under increasing scrutiny as Canadian politicians try to convince U.S. President Donald Trump that they are cracking down on the northern border to avoid tariffs that could cripple Canada's economy.

Trautman and Cozine say the rock barriers are a blunt instrument trying to solve a complex challenge.

"All that really does is funnel people to other places. It's really a cat-and-mouse game," Trautman said.

"People will find other ways. That is just the nature of migration."

Cozine said physical barriers on the U.S.-Mexico border serve as a good example.

"We see that tenfold in the Mexican border where people are making huge investments to build tunnels underneath the borders. When there's a will, and there's innovation, people come up with interesting and innovative ways to circumvent physical barriers," he said.

Better intelligence sharing

The key to securing the Canada-U.S. border is co-operation between the two countries, according to Trautman and Cozine.

"Where Canada and the U.S. are most successful is when we're sharing our intelligence, we're doing joint monitoring and enforcement rather than putting up barriers at the border," Trautman said.

She says that includes uncovering the criminal networks that are helping people illegally cross the border. 

Canada and the U.S. developed innovative and collaborative approaches to manage border security after 9/11, the experts said, including the signing of the Smart Border Declaration and an associated 30-point action plan that introduced new measures such as the Nexus program, common standards for biometrics and permanent resident cards for all new immigrants arriving in Canada.

Then in 2011, the two countries issued a declaration to work together to address threats within, at, and away from their borders under the Beyond the Border Action Plan.

Cozine and Trautman say they're concerned about whether the co-operation between Canada and the U.S. will continue under the current Trump administration, given that the border declaration ended in 2016-17 and nothing as substantial has replaced it.

Unlike in the post-9/11 years, Trautman said little has been accomplished to advance a shared approach to the border in recent years, with some exceptions, such as the 2023 agreement between former president Joe Biden and Prime Minister Justin Trudeau to allow Canada and the U.S. to turn back migrants looking to make asylum claims at unofficial points of entry.

"Canada and the U.S. have done some really neat things. But I don't see that co-operative relationship playing out anytime in the next four years," Trautman said.

"Now we are facing an incredibly antagonistic and aggressive tone set by the Trump Administration and a unilateral approach to international relations."