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Relentless DUI attorney in Aspen, Colorado

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Notable Houston DWI Victories

not guilty

DUI Per Se – DUI – DWAI – Weaving / People of State of Colorado v. S.G.

Moffat County


.194 Breath DUI Per Se, DUI, DWAI, Weaving NOT GUILTY on all counts. My first trial in CO and boy was it interesting. Local counsel came down with Covid on Monday and the next trial date wasn’t until November. Nothing to it, but to do it!  Flew into Hayden and made it to Craig, CO (pop 13k) to try this case with 4 charges at 10pm Tuesday night. Amanda Culbertson flew with me and was a real trooper and brought science that this county had never seen.

Client was pulled over for weaving on a two lane mountain road while pulling a full loaded trailer. Yet video only showed him barely touching the lines. He admitted to having 2 beers at lunch 3 hours ago and looked great on video. Then blows a ridiculous .194. The lab gave us very little discovery so, we couldn’t really audit the machine. We caught a 20 min observation violation but, CO doesn’t have a similar TX 38.23 exclusionary rule so the result still comes in. Whatever the issue was, the result did not add up to what we saw on video.

Voir dire was done with no juror forms, rather the first 12 just answered the questions on the board one by one as the mic was passed around. They allow the breath test in to evidence with the Trooper just swearing he did everything correct.  He was a highly decorated SFST instructor, DRE and 9000 operator.  He even got the MADD award in 2021. But man was he upset after cross exam. He sat through the whole trial and waited for the verdict. I thought he was going to follow us out of town, but he stormed off in the other direction.

Amanda was instrumental in catching the Trooper lying on his 20 minute deprivation period and broke down the video minute by minute and was able to explain all the sounds on video and how it correlated to what the operator was doing on the 9000. I wove a disconnect defense from the beginning and closed it out with a lot of emotion.

The jurors were all very attentive and happy to be there. Many love crime novels and watched all the crime shows. They laughed, learned and gave their hearts and time to this case. Thank you to that jury for remaining true to their doubts and not blindly believing some ridiculous number. I know they will remember this verdict for the rest of their lives and be proud of the day they gave our client his freedom and good name back.

Just as I was telling the Judge I had to leave and local counsel would zoom in for the verdict. They dinged that they had a verdict. Received the verdict and my client was shaking and crying. Culbertson and I took a few photos and made it to the last flight with 14 minutes to spare.

Judge Schneider ran a very fair and efficient trial and was very patient with me figuring out the minute differences between CO and TX law and trial issues. DA was pleasant to deal with. And the Trooper…. Same thing, different state.

Thanks to my wife and associates for holding down the Houston office and letting me spread my wings. Thanks to my office for always having the file well prepared and making my life easier.

When we drove up Wednesday morning and I saw a totem pole out front of the court, I knew it was a good omen. Thanks to God for lining it all up.

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Mark Thiessen


DUI/DWAI Defense Attorney in Pitkin County

“I’m a Board Certified, trial-tested Super Lawyer focused on fighting for my client's freedom. If you hire me as your DUI attorney in Aspen, I’m available 24/7, because, at the end of the day, I work for you. Me being Board Certified in DUI Defense by the National College for DUI Defense means my clients can count on specialized, expert representation that most firms simply can’t deliver.”

What to expect?

Thiessen Law Firm is well-known for expert-level DUI defense attorneys and aggressive, trial-tested criminal defense techniques that enable us to fight like no other on your DUI case. Our trial attorneys not only fight for positive case outcomes, we also care deeply about the overall well-being of our clients.

Why Choose Thiessen Law Firm?

  • Proven DUI or DWAI Lawyer
  • Aggressive Criminal Defense Attorney
  • Board Certified in DUI Defense by the National College for DUI Defense
  • Super Lawyer (2013 – 2021)
  • ACS/CHAL Lawyer Scientist
  • Free DUI & Criminal Charge Case Evaluation
  • No Hourly Rates
  • 24/7 Accessibility
Mark Thiessen
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DUI attorney in Aspen and Pitkin County, CO that will fight for you

Mark Thiessen, the founding DUI defense attorney at Thiessen Law Firm, never backs down in the courtroom. With Mark, facts take precedence over promises –– he’ll tell the truth about your DUI case. Our team of attorneys hold honesty and virtue in highest regard and it is the foundation of ensuring your case ends with a satisfying, positive outcome.

When you get a DUI or DWAI or other criminal charge in Aspen or Pitkin County, your life is changed, no matter the verdict. When you hire Mark Thiessen from Thiessen Law Firm, he will fight to make sure that you can continue to live the life that you want. You’ll never feel forced into taking a deal that you don’t want, or accepting terms you don’t fully understand. With Mark’s expertise in DUI and forensic law, he can provide clients with the knowledge needed to fight for their rights effectively and fairly.


Charged with a DUI or DWAI in Aspen?

You only have 7 days to save your driver’s license

Whether you’re being charged with a DUI, DUI first offense, or DUID (DUI - drugs) in Colorado, you must act fast if you want to save your license. It is required that you request a DMV hearing within 7 days after your DUI arrest, or your license will be automatically suspended for 9 months. If you hire Aspen DUI attorney Mark Thiessen before then, he will request the hearing for you and fight to help protect your driver’s license.

Stop Your Suspension

Happy Clients

They turned what seemed like an impossible case into something with an unexpectedly amazing outcome

“Mark Thiessen is a very knowledgeable, honest, and trustworthy attorney. He and his associates work very hard, and are readily available anytime you need them. They fight for their clients yet maintain a polite and respectable manner in the courtroom. For me, they turned what seemed like an impossible case into something with an unexpectedly amazing outcome. I would highly recommend Mark Thies...

The Best Lawyer in the Industry

“I chose Mark Thiessen to represent me in a DUI / DWI case and it was the best decision that I could have made. Upon meeting with Mark – I immediately knew that he was the right attorney to represent me and give me the best opportunity to win my case. Mark is an expert attorney with a work ethic that is second to none. He is always available. He is a master of his craft and will give you the be...

Fantastic Lawyer

“I would HIGHLY recommend hiring Mark Thiessen as your attorney for any criminal case. He is extremely knowledgeable of the court system and what actions can be taken pre-trial in order to have the best outcome at your court date. I was put on probation for a DWI a year previous to hiring Mark as my attorney. I failed to complete the requirements in order to get off of probation. My probation w...

I couldn’t have gone with a better Law Firm

“I have to start off by saying how thankful I am that my case was dismissed. I never thought I would need a criminal lawyer but life happens. Mark kept me informed during the entire process. He had a game plan from start to finish. I couldn’t have gone with a better law firm.”

It was the best decision I could have made

“I’m a lawyer. I made a mistake one night and was arrested for suspicion of DWI. As a lawyer, it’s extremely difficult to trust your case to another lawyer. It’s ingrained in your bones to want to be in control, but you can’t because no matter what you’ve read on the internet or seen on TV, you don’t know that area of law, or the criminal judges, or the prosecutors, and the reality is all of th...

You Cannot Compare Anybody with Mr. Mark!

“I was accused by my own wife. It was a painful incident that happened in my life. She said to the police that I was threatening to kill her and beat her. She did this to be because she was looking for a lot of money from me and I couldn’t give her the money. She was so bad that she even made proofs with the doctors. There were witnesses from doctors and nurses and even some voice recordings. S...

If You Want a GREAT Lawyer, Mark Thiessen is Your Man

“I found Mark Thiessen through several of my friends. I was having serious issues with the lawyer I had at the time. He kept telling me I was going to jail when I had done nothing. He did not believe me, and I believed he was gonna have me put in jail and not fight for my innocence. From the moment I met Mark Thiessen, I knew he was going to do everything for me to keep me from that horrid jail...

Mark Thiessen is a Jedi Master of his craft.

“Mark and his team have a keen and tactical approach to handling your case, yet still manage to maintain a lot of empathy in their communication with you. A rare combination indeed. They definitely made this process of navigating the court system as smooth as it could possibly be. Things such as answering my texts late at night even on the weekends, and being there in person at the office fo...

This is the only lawyer you should choose for your peace of mind

“Everyone at the Thiessen Law Firm welcomed me and my family but most importantly they were clear in their answers to the many questions I had. Never doubted a positive outcome as I could see their expertise and the way they would be relaxed and calm on going about their business as if you were watching a perfectly synced movie! Ultimately Mr. Thiessen came through for my case and the most incr...

If Mark can’t get you a win, nobody can

“Simply put, Mark Thiessen is a criminal defense all-star. If he can’t get you a win, nobody can. I’ve worked with Mark and his team on two very different cases, and both times I’ve been blown away by the level of honesty, strategy, and respect that Thiessen Law Firm brings to the table. You can feel the difference the second you step in the courtroom with Mark by your side. The time he has tak...

Choosing a DUI attorney in Aspen

If you or a loved one are fighting a DUI or DWAI in Pitkin County, choose an attorney you can trust. It can be easy to pick the first lawyer you see on the internet, but it isn’t guaranteed they’ll be a good one. Don’t just look for any “lawyer near me,” look for a Colorado DUI attorney who wins.

Don’t gamble with your freedom and reputation. Even DWAI or a DUI first offense can be life-altering. At Thiessen Law Firm, we work tirelessly and fight aggressively to protect our clients’ rights against criminal charges.

In addition to being one of the youngest Super Lawyers in the field, Mark Thiessen is Board Certified in DUI Defense by the National College for DUI Defense, DUI Law by the DUI Defense Lawyers Association, and is an ACS/CHAL Lawyer Scientist — the highest form of scientific recognition available for lawyers.

What does all this mean? That Mark Thiessen does not back down in the courtroom because he has the unique expertise to fight DUI charges effectively. He will fight for you like you are his own family.

To get a DUI attorney on your side, request a free consultation with Mark Thiessen today.

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