Keith has been practicing law since 1978 with a focus on personal injury, workers' compensation, product liability and Radiation Exposure Compensation Act (RECA) cases. He is a shareholder of Killian & Davis, PC, in Grand Junction, Colorado. He is a past president and current board member of the Colorado Trial Lawyers Association and a Leaders Forum Member of the American Association for Justice.

Keith has represented injured workers and survivors of those who died in coal mine, methane or hydrocarbon explosions and roof falls. He has represented clients involved in catastrophic propane and toxic chemical explosions and fires. He has a great number of clients who have been awarded administrative benefits due to radiation exposure resulting from uranium mining, milling, ore hauling and processing. He has represented clients in product liability matters including air bag and propeller strike cases. The firm has a large motor vehicle collision trial practice.

Keith earned his J.D. from the University of Colorado, School of Law in Boulder. Keith served as a Judge Advocate General and was promoted to Major in that capacity while in the US Air Force. He was a Colorado State Public Defender. He is or has been a member of the Navajo Nation Bar Association, the Plaintiff Employment Law Association, the National Employment Law Association and the Faculty of Federal Advocates. He has helped draft and has proposed legislation at the state and federal level. He currently serves on the Legislative Policy Committee of the Colorado Bar Association. He has taught CLE classes on a number of subjects. 

In 1994, the National College of Advocacy designated Keith as a Trial Advocate. The Colorado Bar Fellows has recognized Keith as practicing in the top 5 percent of his profession in the practice area of personal injury. Keith was selected as one of the Top 100 Trial Lawyers by The National Trial Lawyers for 2011.