Amid national debate about immigration and the rights of people lies another relevant and troubling issue, one which is becoming alarmingly clear for both citizens and non-citizens in the United States. According to City Watch, the new civil liberties fight might be over breathalyzer tests.

Driving under the influence (DUI) in the United States typically refers to operating a motor vehicle while impaired by alcohol. A motorist is usually charged with DUI if his or her blood alcohol content (BAC) is .08 or more, though in some cases he or she may be arrested for a lower BAC. The problem is that the tests used to gauge BAC can be faulty, and discrimination and racial profiling both play a role in who gets pulled over to begin with.

A DUI arrest is enough to have negative consequences on a person’s life — even without conviction. Aside from the social repercussions at work, school, and personally, the monetary cost of a DUI charge in the United States after fees, fines, and representation amounts to an average of $10,000.

Many arresting officers decide to administer a breathalyzer test, as well as other field sobriety tests, if a driver seems impaired. What’s problematic is that breathalyzer tests is not always as reliable as they seem.

Compounding this problem, according to City Watch, is the fact that police pull over more people of color — blacks and Latinos — than Caucasians, and have since the 1980s. A policy under President Ronald Reagan allegedly encourages police to use minor traffic violations as an excuse to pull people over to investigate for other crimes.

In Arizona, racial profiling has been a tense issue since 2010, when Governor Jan Brewer signed into law Senate Bill 1070, which allows police to “arrest a person if the officer has probable cause to believe that the person has committed any public offense that makes the person removable from the United States.” Now, activists are calling attention to the problem of racial profiling when it comes to police stopping minorities.

U.S. Border Patrol has set up a temporary checkpoint on Arivaca Road in Arizona, and according to AZ Central, People Helping People, a group that provides humanitarian aid along the border, has taken to monitoring traffic stops along Arivaca Road “to deter abuse and to collect data.”

People Helping People has been monitoring the stops that police perform on Arivaca Road, from the length of the stops, to the condition of the vehicle, to the nationality of the driver. Preliminary data collected by People Helping People indicates that “checkpoint systematically discriminates against Latinos and isn’t deterring illegal immigration or halting the flow of drugs,” according to AZ Central.

Though none of the stops that the group monitored resulted in DUI charges, the data could point to a contributing factor to the number of DUI charges against Latinos and another unjust factor in DUI charges themselves, which calls into question the nature of racial profiling, unreasonable stops, faulty breathalyzer results, and how they all relate to the Fourth Amendment, which is supposed to protect citizens from illegal search and seizure.