A Trial Lawyer You Can Trust

3 common forms of evidence used to prove drunk driving

On Behalf of | May 22, 2025 | Dui

People accused of intoxicated driving face a variety of potential consequences. Drivers who get convicted at trial or who plead guilty to impaired driving are subject to numerous significant penalties. Incarceration, fines and court costs are standard. People can also expect to lose their driving privileges at least temporarily.

Those hoping to avoid those consequences may need assistance as they develop a criminal defense strategy, look into pretrial diversion programs and contemplate plea bargaining. Defendants generally need to understand how the state builds its case to determine how likely they are to prevail if they go to trial.

What evidence usually helps back allegations of impaired driving?

Video footage

Frequently, police officers follow drivers in traffic to record their questionable behavior. The cameras in police cruisers can capture video footage of drivers braking without reason, sporadically accelerating and swerving all over the road. That video footage can make it clear to others that there may have been something wrong with the driver. Recordings of phone calls from others concerned with the driver’s conduct on the road could also serve as evidence to support allegations of impaired driving.

Field sobriety test results

When officers believe someone may be under the influence, they may ask the driver to demonstrate their sobriety. This process usually involves following instructions to perform three standardized field sobriety tests. While there are many reasons why people might fail one or more of these tests other than intoxication, officers often assume the worst. Field sobriety tests are voluntary and can become a key form of evidence for the state in a drunk driving case.

Alcohol test results

When police officers have probable cause to suspect intoxication, they can ask a driver to submit to chemical testing. Unlike field sobriety testing, which is fully voluntary, chemical testing is sometimes legally mandatory. If officers have enough evidence to arrest a driver, that motorist usually has a responsibility to submit to testing. If they fail the test, their test results can help establish that their blood alcohol concentration (BAC) was over the legal limit. If they refuse the test, they may be at risk of administrative penalties.

The exact evidence the state has collected may influence the best defense strategy for a driver accused of intoxication. Fighting back against drunk driving charges requires a thorough review and the support of someone familiar with state statutes.

Archives

RSS Feed

FindLaw Network

Our Practice Areas

Criminal
Defense

Collaborative
Courts

Personal
Injury

Business And
Civil Litigation

Results And
Testimonials

You Need A Fighter On Your Side

Super Lawyers
State Bar Of California | CBLS | California Board Of Leal Specialization | Certified Since 2001
The National Trial Lawyers | Top 100 Trial Lawyers

How Can We Help You?