Meet Our Team

James D. Thorburn

Managing Partner

Jim Thorburn is a nationally recognized and highly experienced litigation and transaction attorney.  Jim Thorburn has been a licensed attorney since 1991. He is one of the founding partners of Thorburn Law Group, LLC primarily located in Greenwood Village, CO with other locations in Las Vegas, NV.  

Jim is a highly knowledgeable and experienced commercial litigation attorney, practicing in both state and federal courts.  From 1991 through 2012, Jim’s primary focus was in commercial real estate and construction law.  In 2012, Jim began to practice cannabis tax controversy law, taking on some of the most notable cannabis tax controversy cases in the nation.   This experience has made Thorburn Law Group a formidable force in cannabis tax controversy.   

Jim had the honor of arguing, on a writ of mandamus, Feinberg v. Commissioner, 808 F.3d 813 (10th Cir. 2015) in front of now Justice Neil Gorsuch.  Justice Gorsuch’s opinion in Feinberg has been described as a “technical loss but an artful win for the cannabis industry.” 

Jim is on the forefront of the current federal and state issues affecting dispensaries and works hard to achieve successful outcomes for his clients. Jim works with state and national legislators to effect positive legislative change for the cannabis industry. He helps dispensaries, grow facilities, and other businesses navigate through complex federal legal issues including tax court and IRS audits. In addition to Section 280E issues, Jim also provides general business representation, and helps dispensaries comply with the regulations under state cannabis laws.

 Jim has received national recognition as a lead litigating attorney in a majority of the cannabis industry’s high-profile cases.  He speaks on marijuana legal issues across the country and is a featured expert for the National Cannabis Industry Association. He has been featured in CNBC, INC. Magazine, MJ Biz Daily, HBO (Vice News), Denver Post, Law360, Yahoo Finance, National Law Journal, The Cannifornian, and others. 

Jim recently received the coveted 2019 National Law Journal Cannabis Law Trailblazer Award.  The National Law Journal has also designated Jim as a national “Lawyer of Distinction” for 2019. 

In his spare time, Jim is actively involved in motorsports and is the President of the Rocky Mountain Region Porsche Club of America, which is one of the ten largest regions in the United States by membership.   He is also a member of  PCA National Audit Committee.

Jim Thorburn has a B.S. in Business Administration from California State University, Northridge and a Juris Doctor from the University of Denver College of Law.  In his spare time, Jim enjoys serving as the President of the Rocky Mountain Porsche Club of America, racing cars, and flying small airplanes. 

Carolyn M. Schaffer

Attorney at Law

Carolyn Schaffer is an attorney at Thorburn Law Group, LLC specializing in marijuana dispensary tax (mainly 280E) and general business matters, as well as commercial real estate, commercial construction, and land use and zoning. Carolyn is also a member of the National Cannabis Industry Association’s State Regulation Committee.

Carolyn has obtained a Juris Doctor from the University of Denver Sturm College of Law, a Master of Science in Legal Administration degree from the University of Denver Sturm College of Law and a Bachelor of Science in Economics degree from the University of Colorado at Colorado Springs.

In her spare time, Carolyn enjoys traveling, spending time with her family, and engaging in fitness activities.

Theresa Mains

Attorney at Law

As an Attorney, with a Master's Degree in Accounting concentrating in forensics, and a Certified Fraud Examiner, Theresa Mains has a strong background in complex business litigation and consulting, fraud investigations, business insolvency and bankruptcy, civil and criminal white collar crime litigation and tax controversy. Theresa offers extensive financial experience and a deep understanding of critical financial litigation issues. As both accountant and attorney, Theresa has worked in a range of legal and consulting engagements since 1997 that involved fraud, tax disputes, bankruptcies, and white collar crime.

Obtained judgment for Fraud and Conversion and award of $100,000 for Victim of Ponzi Scheme in Las Vegas. 

Represented Client during IRS audit and after an analysis of financials, negotiated with the IRS Agent to lessen penalties and interest with a result of over $30,000 credited to client for overpaid taxes.

Dana Tafoya

Office Manager

Joining the firm in 2020, Dana Tafoya's position & role is to represent the firm with an endless vision to grow, manage, and nurture our clients with an emphases on marketing, to help us take us all to new heights.  Dana's passion is helping people & building relationships that last a lifetime.

Dana is a proud native of Colorado.  Her Boys & Doggies keep her busy.  She enjoys concerts, traveling, and riding motorcycles with her husband. 

"The only way to do great work is to love what you do" - Steve Jobs 


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