A DWUI arrest in Rock Springs triggers two cases simultaneously. One is a criminal case filed in Sweetwater County Circuit Court, while the other is an administrative case regarding a license suspension issued by the Wyoming Department of Transportation. Within 20 days of your arrest, you must request a hearing to challenge the suspension. If you miss the deadline, your license will be automatically suspended, regardless of what happens in the criminal case.
Wyoming DWUI Charges in Sweetwater County
Wyoming’s statutes don’t use the word “DUI.” Under W.S. § 31-5-233, the charge is DWUI, which is Driving While Under the Influence. This is what appears on your citation and court paperwork, even though a Rock Springs DUI attorney and a Rock Springs DWUI attorney are handling the same charge.
A DWUI arrest means two things happening in parallel. The criminal case is sent to Sweetwater County Circuit Court, where you face jail, fines and probation. The administrative case goes through WYDOT, which decides whether you will keep your license. These two processes do not wait for each other. You can win the criminal case in months and still lose your license in the next month, because nobody asked for a hearing in time.
The legal threshold for most drivers is 0.08% BAC. Commercial drivers have a lower bar at 0.04%, and drivers under 21 years old can be charged with just 0.02% under Wyoming’s zero tolerance law, W.S. § 31-5-234. However, none of these numbers tell the whole story. You don’t need to have a BAC test to be charged if an officer believes that you are too impaired to safely drive.
You also don’t need to be driving. Wyoming law covers “actual physical control” of a vehicle. Sitting in the driver’s seat with the keys within reach, engine off, parked, can still qualify. Courts look at the whole picture: where you were sitting, where the keys were, whether the vehicle was running. This element is contested more often than people expect.
The 20-day deadline is the part that most people miss. It has nothing to do with the criminal case timeline. It’s a hard administrative cutoff. Once it passes, the suspension takes effect, whether or not you have even seen a judge.
What an I-80 Traffic Stop Turns Into
Interstate 80 runs straight through Sweetwater County, and it’s one of the most heavily patrolled stretches of highway in the state. The Wyoming Highway Patrol Troop B puts a lot of resources into this corridor.
Two things drive the volume of traffic. First, it’s a trucking country. Commercial drivers travel through Rock Springs all the time, and a DUI on I-80 in Wyoming for someone with a CDL has consequences that extend far beyond the Wyoming courtroom. Secondly, the local energy industry, oil, gas, and trona mining mean a large working population moving between job sites, towns, and homes at all hours.
Out-of-state travelers also add to the numbers. Plenty of drivers passing through I-80 do not realize Wyoming’s DWUI laws apply to them fully: the same penalties, the same 20-day period, everything the same. There is also active construction on I-80 from mile markers 101 to 108 since 2026, and construction zones often bring more police presence with them. Wyoming is among the top states in the country for traffic fatalities involving alcohol per capita. This statistic drives enforcement priorities nationwide, and Sweetwater County is no exception.
DWUI Penalties in Wyoming
Penalties escalate quickly with each prior offense within a 10-year period. Here’s what you face.
First DWUI Offense
A first offense is a misdemeanor. It can result in up to six months in jail, a fine of up to $750, and a license suspension for 90 days. If your blood alcohol concentration (BAC) was 0.15% or higher when you were driving, you must install a mandatory ignition interlock device when you return to the road. The court also requires a substance use evaluation.
Second DWUI Offense (Within 10 Years)
This is where mandatory jail time begins. A second offense within 10 years results in a 7-day minimum sentence that a judge cannot reduce, up to a maximum of six months, fines ranging from $200 to $750, a one-year license suspension, and the requirement to install an interlock device for one year.
Third DWUI Offense (Within 10 Years)
A third offense brings a mandatory minimum of 30 days, up to 6 months in jail, fines ranging from $750 to $3,000, 3 years suspension, and 2 years with an ignition interlock device.
Felony DWUI (Fourth or Subsequent Offense)
A fourth DWUI in 10 years is a felony in Wyoming, up to seven years in prison, and up to $10,000 in fines, with a 5-year mandatory license revocation and an interlock device requirement that lasts for life, reviewed by the court every five years. For more information on how these charges are applied, see our felony DUI page.
If You Live Out of State
Wyoming belongs to the Interstate Driver License Compact. If you are convicted of DWUI here, your home state will find out and treat it the way they would treat a conviction that occurred locally, applying their own suspension rules in addition to Wyoming’s.
Wyoming will also suspend your driving privileges here for the same periods as a resident would face. Your physical license is typically confiscated at arrest and you are issued a 30-day temporary permit to get home. The 20-day ALS hearing deadline applies to you exactly as it does to a Rock Springs resident with or without a temporary permit.
Defense Strategies in Rock Springs DUI Cases
Not every DUI arrest results in a conviction, and not every breath test result is accurate. The defenses available in a DWUI case depend on the specific facts, but some of the most effective approaches include:
Challenging the traffic stop.
Police need reasonable suspicion to pull you over. If the stop wasn’t legally justified, evidence gathered afterward may be suppressible.
Attacking the breath or blood test.
Breathalyzer machines need to be calibrated and maintained correctly. The officers have to follow specific procedures when administering the test. Blood draws have their own chain of custody requirements. Any interruption in that chain is a problem.
Questioning field sobriety test administration.
Standardized field sobriety tests (SFSTs) are only reliable when administered correctly under the right conditions. Weather, road surface, footwear, and medical conditions can all affect performance in ways unrelated to intoxication.
Examining the officer’s observations.
The officer’s testimony regarding your driving, appearance, and behavior becomes part of the record. Christina Williams understands how those observations are framed in police reports because she spent years reading them from the prosecutor’s side.
What Just Criminal Law Brings to Your Rock Springs DUI Defense
Most criminal defense attorneys can tell you what the law says. Fewer can tell you how a specific prosecutor in a specific county is likely to approach a case, and what arguments actually move the needle in that courtroom.
Christina L. Williams worked as a prosecutor before founding Just Criminal Law. That experience isn’t just a line on a resume. It means she evaluates every DUI case from the prosecution’s perspective first, identifying the weaknesses in the state’s evidence before they do. Just Criminal Law handles DUI defense throughout Wyoming, with specific experience in Sweetwater County courts.
The firm is trial-ready. Not every case goes to trial, but having an attorney who is genuinely prepared to take a case to a jury changes how prosecutors engage. It changes the offers they make. It changes the dynamic of the entire case.
