How The Police Build A DUI Case

Whether you are dealing with the cops out in the world or have been ordered to appear to answer a charge, it's a good idea to understand how they build their cases. A DUI lawyer services provider looks at each of these three elements of the case to see where the police might have gotten something wrong, and you should, too.

Step 1: Reasonable Suspicion

This is the most limited justification a cop can provide for interfering with any member of the public. Reasonable suspicion arises when the current evidence indicates that a crime may have been committed or is currently in progress. Generally, the courts want to hear that the cop arrived at this limited reasoning based on an informed hunch.

If you ever read the police news blotter's description of different DUI charges, you'll notice the mention of things like the driver went over the center line multiple times or was swerving. This is reasonable suspicion being established.

Notably, reasonable suspicion is a lower-clearing standard of proof than probable cause. For this reason, the police can only detain you for a few minutes under reasonable suspicion. A DUI lawyer will frequently try to poke holes in the original claim of reasonable suspicion and ask the court to toss the entire case.

Step 2: Probable Cause

With the few minutes they have at the start of a stop, the cops try to establish probable cause. This is the justification for more aggressive tactics, particularly breath tests and even blood samples. It's worth noting that the invasiveness of a blood test means you can refuse it and force the cops to get a warrant.

Getting to probable cause requires pulling together better information. This is why the cops ask motorists if they've been drinking. An admission makes it easy to jump straight to doing a field sobriety test. Stumbling during the field test is grounds for administering a breathalyzer.

Step 3: Arrest and Filing of an Affidavit

The final step involves concluding that a DUI violation has occurred. While a BAC reading above the state's legal limit is the typical basis for arrest, a cop can charge someone based purely on their own judgment. That's a more difficult case for them to prove, but they can cite evidence that a person was on undetectable substances. This may include pupil dilation, disposition during interrogation, or the presence of drug paraphernalia. They then file an affidavit telling the court why they concluded a DUI had been committed.

A DUI lawyer can help you determine if the police made a mistake or failed to meet the requirements to charge you during any of these steps. 

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