About Michael David
Michael David Mercer built his legal foundation at the University of Texas at Austin, earning a Bachelor of Arts in 2008, and then completed his J.D. at Mississippi College School of Law in 2012, where he trained in trial advocacy. The record of his education shows formal preparation for courtroom work. He carried that foundation into practice in Texas and federal courts.
Early years after law school were spent learning litigation fundamentals and court procedure. His training in trial advocacy informed those formative years. He has since appeared in Texas state courts and in federal proceedings. He is also admitted to practice before the U.S. Court of Appeals for the Fifth Circuit, which expands the range of matters he can handle beyond trial courts.
Colleagues describe Mercer as methodical in preparing cases. He breaks down complex records into discrete issues and tests them in motion practice and at hearings. That approach suits both trial work and appellate briefing. He has experience drafting pleadings, arguing motions and preparing appellate briefs for review in the Fifth Circuit. He tends to balance close attention to factual records with targeted legal argument.
Mercer practices at Mercer & Keirnan. At the firm he works alongside other litigators on contested matters that require courtroom presence and federal appellate advocacy. His practice regularly requires travel to state courthouses across Texas and appearances before federal panels. He is comfortable handling hearings and oral argument, roles that dovetail with his trial advocacy background.
Outside the courtroom, he has engaged in case development and client counseling aimed at clarifying legal options. He prepares clients for the mechanics of trial and appeal. His work frequently involves coordinating fact investigation, witness preparation and the drafting of dispositive motions.
Peers note his steady courtroom demeanor and clear oral presentation. He tends to favor concise legal writing over dense exposition. That preference is apparent in his briefs and in how he structures arguments for judges at both the trial and appellate levels.
As of 2026, his practice remains based at Mercer & Keirnan. He continues to represent clients in Texas state courts and before the U.S. Court of Appeals for the Fifth Circuit.
