San Diego County residents live in Border Patrol’s enforcement zone. Here’s what that means

Federal agents, just like local law enforcement officers, must meet certain legal thresholds in order to carry out certain activities in the furtherance of their mission. For Border Patrol, that mission is to apprehend violators of federal immigration law. 

Federal agents need reasonable suspicion to: 

• Pull a driver over 
• Detain someone. If they ask if they are free to leave and the agent says no, they are being detained.

And they need probable cause to: 

• Make an arrest.
• Search someone’s vehicle or belongings (unless they are given permission).

According to the Supreme Court, an officer has reasonable suspicion if they can “point to specific and articulable facts which, taken together with rational inferences . . . reasonably warrant” a person’s detention. In the context of immigration law, agents need reasonable suspicion that a civil or criminal immigration violation has occurred.

And probable cause is defined as when “the facts and circumstances within the officers’ knowledge … are sufficient in themselves to warrant a belief by a man of reasonable caution that a crime is being committed.”

In general, federal immigration agents can only enforce federal immigration law, so they can’t get a driver in trouble for speeding, for example. 

However, agents can use that a driver was speeding as part of their basis for reasonable suspicion or probable cause. 

In some parts of the country, agents can rely in part on a person’s race and ethnicity in determining that basis, but those factors cannot be the sole basis for reasonable suspicion or probable cause. Civilians can always choose to remain silent or decline to answer questions without a lawyer.

There are as many as 13 checkpoints, temporary or permanent, operating in Southern California, including on the heavily traveled westbound Interstate 8 in Pine Valley, northbound Interstate 5 in San Clemente, and northbound Interstate 15 near Temecula, and along more rural routes near Campo, Ocotillo and the Salton Sea. 

When passing through a checkpoint, Border Patrol can ask the driver and passengers a few questions related to their immigration status and can visually inspect the outside of the vehicle. 

Agents may also use drug-sniffing dogs around stopped vehicles or send vehicles to a secondary inspection area for further, but brief, questioning and visual inspection. 

They still need reasonable suspicion to question drivers longer or detain drivers. Agents cannot arrest drivers or physically inspect vehicles or belongings without probable cause. 

It’s a felony to flee an immigration checkpoint. 

When Border Patrol agents conduct “roving patrols,” during which agents drive throughout the enforcement zone looking for immigration or other federal violations, they need to have reasonable suspicion of criminal activity to pull over a vehicle and probable cause to search the vehicle. 

It is illegal for agents to pull over vehicles based solely on the race or ethnicity of the driver or occupants, but in practice, it happens, according to the ACLU.

Border Patrol can board buses and trains within the enforcement zone to question passengers about immigration status, travel plans and luggage. Passengers can refuse to comply or answer questions, but doing so could lead to prolonged questioning. 

United States citizens are not required to carry proof of their citizenship with them at all times. Others over the age of 18 with legal immigration documents are required to carry them at all times. 

If an agent is questioning a passenger and they do not feel free to leave, the agent needs reasonable suspicion to detain them. At some point, when the detention goes from brief to prolonged and becomes an arrest, the agent needs probable cause.