Drunk-driving convictions could increase because of the Supreme Court's recent ruling

Last week, the Supreme Court ruled that police officers can administer warrantless breathalyzer tests to people suspected of driving drunk.

The case, Birchfield v. North Dakota, effectively criminalizes the refusal to submit to a breathalyzer test and affects laws in 11 states.

The outcome will likely lead to an increase in drunk-driving convictions across the country, according to Derek Andrews, a defense attorney at the DUI Foundation, the organization linked to the viral "silent" drunk-driving checkpoint hack.

The Fourth Amendment protects against unreasonable searches and seizures, although laws vary state-by-state. Many lawyers openly encourage their clients to refuse a breathalyzer because prosecutors have a harder time landing convictions with less evidence. Depending on the probable cause, refusing to take a pre-arrest breathalyzer likely won't result in a license suspension, but in many states, like New York, refusing a post-arrest breathalyzer could lead to automatic license suspension of varying durations.

With the Supreme Court's decision, however, there could be "an increase in the number of chemical test results," Andrews wrote in an email to Business Insider. People might be more likely to submit for fear of the certain legal repercussions. Chemical tests can be a breathalyzer, blood draw, or even a urine sample.

To put it simply, more people submitting to breathalyzer tests means that states and prosecutors will have greater evidence against them.

While a state should be able to ask for a warrantless breathalyzer test, and even a blood draw, states should not be able to criminalize the refusal of the test, according to Andrews.

"It is a fundamental premise of our criminal justice system that it is the government's burden to prove beyond a reasonable doubt that someone is guilty of a crime, and it is the government's duty to collect evidence and develop a case," Andrews wrote. "It is not, however, a person's duty to give that evidence to the government."

Issuing criminal penalties, however, could also encourage people to refuse a breathalyzer.

"This country is simply going to have more criminals because the government has chosen to criminalize a refusal to provide (potentially) incriminating evidence to law enforcement," Andrews wrote. ".... There are other ways of combating DWI/DUI than convicting more people of crimes."

It's worth nothing the Supreme Court differentiated between breathalyzer tests and blood tests, arguing that because blood draws are more intrusive, states may not demand them without a warrant.

The decision combines three cases but centers on an incident in North Dakota, in which a man, after crashing his car, took a breathalyzer which found his blood-alcohol concentration (BAC) at three times the legal limit. He didn't, however, agree to a blood draw was charged with a misdemeanor.

While Justice Sonia Sotomayor sided with the majority's opinion on warrantless blood tests, she took issue with the Court "establishing exceptions to the warrant requirement" and suggested that states should find other ways to combat drunk driving that "do not have the same impact on personal privacy" as allowing warrantless breathalyzer tests.

Andrews, for his part, agrees.

"The Fourth Amendment is being attacked and our freedoms in this country are being whittled away," he wrote.