Mr. Keirnan or Mr. Mercer - John P.

Houston criminal defense lawyer John P. "Casey" Keirnan has practiced criminal defense in Houston and the surrounding counties for 36 years. After four decades, Mr. Keirnan has mastered the art of defending those accused of a crime. He has successfully defended all misdemeanor and felony charges and is often used as a source of advice for fellow criminal defense lawyers in the community. In 2014, the Harris County Criminal Lawyers Assocation voted Mr. Keirnan "Lawyer of the Year" in recognition of his talent and his unmatched dedication to his clients. He is regarded by both judges and fellow attorneys as one of the best criminal defense lawyers in Houston. ​ In 2010, Mr. Keirnan was awarded the "Unsung Hero Award" by his colleagues in the Harris County Criminal Lawyers Association after becoming the first attorney in Texas to succesfully argue a motion declaring the death penalty statute unconstitutional. Mr. Keirnan has a reputation of going above and beyond the duty he owes to his clients. His candor and professionalism in the courtroom are well known throughout the Harris County Criminal Courthouse. Mr. Keirnan is one of only a few criminal defense lawyers approved by the Second Judicial Administrative District of Texas to represent individuals accused of capital murder.