Mark Ryan Thiessen
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Mark Thiessen is a criminal trial lawyer and the Chairman/CEO of the Thiessen Law Firm in Houston, Texas. Mark earned the American Chemical Society-Chemistry and the Law (ACS-CHAL) Forensic Lawyer-Scientist designation, which is the highest form of scientific recognition available for lawyers. Mark is a frequent legal seminar lecturer, author of numerous published legal articles, and a LawLine and HBA faculty member. Mark is the current DWI Committee chair for Texas Criminal Defense Lawyers Association (TCDLA), on the Board of Directors for Harris County Criminal Lawyers Association (HCCLA), and a Charter Member and Director for DUI Defense Lawyers Association (DUIDLA). Mark is a Texas Super Lawyer and was awarded the 2012 Unsung Hero Award by HCCLA.Stories from Mark Ryan Thiessen
Friday, February 14th, 2020
In the heat of trial, all trial attorneys fight vigorously for their DWI clients. In that fight, it’s understandable that you want to destroy the officer, destroy the Standard Field Sobriety Tests (SFSTs), and vindicate your client.
Friday, November 8th, 2019
Together, House Bills 20482 and 35823 refashioned Texas DWI law and punishment—and finally abolished surcharges. Kind of.
Friday, March 9th, 2018
“Ma’am, we regret to inform you, but your son was killed by a drunk driver.”
“Ma’am, we regret to inform you, but your son has been arrested for killing someone while driving intoxicated.”
Tuesday, May 9th, 2017
Whether blood samples used in forensic science Driving While Intoxicated (DWI) testing can be affected by endogenous ethanol production is a recurrent and yet unresolved defense. The basis of endogenous ethanol production is whether microbial growth can occur to falsely elevate the ethanol concentration in forensic blood samples.
Saturday, November 21st, 2015
The sweet acrid smell of a freshly lit cigarette danced inside his nostrils, seeping into his unconscious brain, waking him. His eyelids twitched and tremored, but did not open. It was an auto somatic response; like a mother drawn to her crying babe. Not something sought out. It was more a keening allure; an impulse impossible to ignore. Vices. Lovely reliable vices.
Thursday, August 13th, 2015
However, Texas is currently transitioning to the Intoxilyzer 9000 and training breath test operators through local technical supervisors. Implementation of the Intoxilyzer 9000 was scheduled for Summer 2015, but due to software issues and bugs, the 9000 has not been approved for evidential use.
Saturday, December 6th, 2014
Finally the day has come: Written on the face of the State’s file, in big red letters, is the blood test result. Most attorneys cringe when the lab result reveals a blood alcohol concentration over a 0.15.
Wednesday, June 4th, 2014
"We, the Jury, find the defendant not guilty.” Makes your hair stand on end, drops the weight from your shoulders, and weakens your knees. No sweeter words are ever heard by criminal defense attorneys standing shoulder to shoulder with their clients.
Tuesday, October 1st, 2013
The era of the total-refusal DWI case is quickly coming to a close in Texas. Gone are the days of refusing a breath test without concern for something more invasive. DWI blood test trials are the future for the criminal trial attorney.
Thursday, September 6th, 2012
“May it please the court, opposing counsel…Ladies and Gentlemen, thank you for listening to all the evidence. . . .” Just about this time, juries’ eyes glaze over; they shift focus and start daydreaming. You have just lost the jury.
