Inevitable Discovery Doctrine and Why Police Can’t Arrest You for What You Might Potentially Do
The case turned on a common but often misunderstood concept—the inevitable discovery exception to the exclusionary rule. The State tried to stretch that rule too far. The court said no.
What Happened?
Police pulled over a car for a turn signal violation. The driver was arrested for DUI. Hector Abonza, the passenger, stayed in the car. Officers smelled alcohol and said Abonza had slurred speech and glassy eyes. He refused to give ID and said he planned to walk away.
Before he stepped out, officers told him he was detained for public intoxication. When he finally exited the car, he stumbled. Officers immediately arrested him.
Abonza was charged with three offenses:
- Public intoxication
- Refusing to disclose identity
- Interfering with an arresting officer
He moved to suppress the evidence. His argument? Police arrested him without enough cause. The trial court agreed. The charges were dismissed.
The State’s Argument
On appeal, the State didn’t claim the arrest was valid from the start. Instead, it argued that officers would have had probable cause soon after. Abonza’s intoxication, they said, would have become obvious as soon as he started walking away. So, under the inevitable discovery rule, the evidence should stay in.
The Court of Appeals disagreed.
What the Court Said
The court focused on the timeline. At the moment of arrest, police didn’t yet have enough evidence that Abonza was a danger to himself or others. That’s a key part of Utah’s public intoxication law. Without it, there’s no crime.
Yes, Abonza later stumbled. But that happened after the arrest. The court said police can’t justify an illegal arrest with something that happened after the fact.
The court also rejected the State’s use of the inevitable discovery doctrine. That rule applies only when discovery is truly certain—not just likely. Here, many outcomes were possible. Abonza might have walked safely down the road. He might have called for a ride. Or he might have done something dangerous. But none of that had happened yet. So there was no way to say discovery of the crime was inevitable.
Why It Matters
This case draws a clear line. Police can’t arrest someone because they think a crime will probably happen. Probable cause must be based on facts, not forecasts.
It also clarifies the limits of the inevitable discovery doctrine. The rule is narrow. It’s meant for cases where legal discovery was already in motion. It’s not a backdoor way to save evidence from an unconstitutional arrest.
Bottom Line
The Court of Appeals’ ruling in State v. Abonza affirms that constitutional protections apply in real time. The inevitable discovery doctrine, while narrow and practical in scope, does not provide cover for arrests made in anticipation of future conduct. For practitioners, it’s a timely reminder that the rules of engagement are firm: probable cause must precede the arrest, not follow it.