• vcard
  • Education
    • J.D., cum laude, Harvard Law School, 1990, Editor for Environmental Law Review
    • B.A., summa cum laude, University of Vermont, 1985, Political Science, Environmental Science; Phi Beta Kappa
  • Court Admissions
    • State of Colorado, 1990
    • U.S. Court of Appeals, Ninth Circuit
    • U.S. Court of Appeals, Tenth Circuit
    • U.S. Court of Appeals, Eleventh Circuit
    • U.S. District Court, District of Colorado
    • U.S. District Court, Middle District of Florida
    • U.S. District Court, Eastern District of Washington
    • U.S. District Court, Northern District of Oklahoma
    • U.S. District Court, Southern District of Ohio
    • U.S. District Court, Northern District of Ohio
Colin Deihl is a trial lawyer for complex business disputes.  He handles  all stages of litigation, including jury and bench trials, class actions, arbitrations, mediations, and regulatory hearings. He has more than 30 years of standup courtroom experience communicating highly technical factual, regulatory, and legal issues to generalist judges and juries. Colin’s cases often involve strategic coordination with public and governmental relations teams. Colin is also trusted by his clients to lead sensitive internal investigations and compliance counseling. 

 Colin has handled cases involving a wide range of businesses including brewers, energy providers, health care, real estate owners and developers, sports and entertainment, and utilities. He has litigated cases throughout the United States, including putative nationwide class actions.  

For his real estate and energy clients, Colin handles conflicts involving real estate agreements and land use issues.    


Lead counsel defending large hospital system against putative class action asserting improper collection of subrogation payments from Medicaid recipients.  
Defend client in several actions asserting improper attempts to prevent member from withdrawing from power generation cooperative. 
Lead counsel defending theme park and entertainment company in related putative class actions, one in California state court and one in Florida federal court alleging improper renewal of annual passes.
Lead counsel defending up-stream oil and gas clients against Clean Air Act citizen suit asserting failure to obtain major source permits before commencing operations.    
Lead counsel defending public utility against Clean Air citizen suit asserting failure to continuously monitor opacity.  
Defend against nationwide putative class action asserting breach of contract and violation of consumer protection act arising out of alleged overcharges.
Lead counsel for professional sport organization in putative nationwide class action alleging consumer fraud and breach of contract claims against both the sport organization and its 92 member board of directors.  
 Preliminary injunction action against State of Colorado for improper calculation of provider fee against hospital clients.
Defended hazardous waste incinerator against citizen suit claim for violation of Clean Air Act permit in federal court in Ohio. Case involved complex technical interpretation of Title V permit and continuous emission monitoring requirements.              
Trial counsel for construction company resulting in $23 million jury verdict in favor of client involving breach of contract and fraud claims in runway paving contract.
Defended large public utility in multiple lawsuits brought under the Clean Air Act alleging violations at the Cherokee Station power plant in Denver and the Comanche 3 power plant in Pueblo.