Mark Grueskin's law practice occurs at the junction of all three branches of government.


In the courts, Mark litigates high profile policy and political matters, using trial strategies that the Denver Business Journal said "emphasize innovation over convention." For Mark's landmark court victories, Law Week Colorado awarded him Lawyer of the Year honors in 2009, 2012, and 2014.


In the law-making process, Mark drafts legislation and ballot measures. He has written a number of successful ballot initiatives, including measures that increased tobacco taxes, instituted background checks at gun shows, and authorized medical marijuana. He helped defeat or keep off of the ballot amendments that mandated draconian fiscal policies for state and local governments, expanded casino gaming to the Denver metro area, and endangered Colorado’s agricultural economy. He regularly advises clients on federal state, and local campaign finance law. Campaigns & Elections Magazine called him "Colorado's best election lawyer, bar none."


Mark represents commercial clients before executive branch regulatory agencies and licensing boards. For instance, he has counseled Colorado's gaming industry for more than twenty-five years. He regularly assists companies with license applications, enforcement actions, and agency rule-making.


Mark also advises non-profit organizations and represents statewide and national trade associations, providing them with formation and operational advice and helping them develop policy or political arms consistent with tax and election laws.


Mark's practice often addresses complex issues of constitutional law. He represents governmental officials before the Colorado Independent Ethics Commission. In trial and appellate courts, he has served as lead counsel for the State of Colorado, the Colorado General Assembly, the Colorado Transportation Commission, and the City & County of Denver. He also represented the 2008 Democratic National Convention as well as 2008, 2012, and 2016 presidential campaigns.


Best Lawyers in America© named Mark as Lawyer of the Year in the fields of Government Relations (2015), Regulatory/Administrative Law (2016), and Gaming Law (2017) in Denver. He has long been recognized as a Colorado Super Lawyer.


In his spare time, Mark coaches high school mock trial teams in the Denver area, including a talented, hard-working, scrappy bunch that was crowned Colorado’s 2017 State Champions.

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