MARK B. O'CONNOR

Mark B. O’Connor

San Jose Attorney for Catastrophic Personal Injury and Appellate Advocacy

Dedicated Representation for Seriously Injured Clients

Mark B. O’Connor, attorney at Shea & Shea in San Jose, is a trusted advocate for individuals and families facing life-altering injuries. As a senior personal injury and appellate advocacy lawyer, he focuses on complex, high-stakes litigation involving catastrophic harm—cases where the medical and financial impact is profound.

Since his admission to the California Bar in 1986, Mr. O’Connor has combined courtroom precision with a deep knowledge of personal injury law. He represents victims of devastating motor vehicle collisions, as well as those injured in construction accidents and cases involving traumatic brain or spinal injuries.

Known for his skill in both trial and appeal, he provides complete legal representation from the first investigation to the final judgment, ensuring each client receives the firm’s full commitment at every stage.

Areas of Practice

• Catastrophic Injury
• Spinal Cord Injuries
• Acquired Brain Injury
• Closed Head Injuries

Practice Focus—Catastrophic Injury Litigation and Appeals

Mark B. O’Connor’s work is defined by two pillars: catastrophic personal injury cases and appellate advocacy. These practice areas intersect frequently, as the most serious personal injury claims often combine complex liability issues with disputed medical evidence that can lead to appeal.

At trial, he handles matters involving:

• Traumatic brain injuries (TBIs) caused by impact, hypoxia, or shear trauma.
• Commercial trucking and car accidents, including rollovers and lane-change collisions.
• Spinal cord injury lawsuits resulting in paralysis or chronic neurological impairment.
• Construction and industrial accidents involving unsafe practices or equipment failures.
• Product defect and premises liability claims where negligence caused catastrophic harm.

Each case begins with a detailed investigation and a strategy developed in consultation with medical and technical experts. Mr. O’Connor’s approach reflects Shea & Shea’s philosophy—relentless preparation and a willingness to take complex cases to verdict when fair resolution cannot be reached.

Because catastrophic-injury litigation frequently involves multiple stages of interaction with the legal system, his dual role as both trial lawyer and appellate advocacy lawyer ensures continuous representation. Clients benefit from the same advocate who understands every facet of the evidence and record, a major advantage when facing post-trial motions or appellate review.

Many of the cases Mr. O’Connor handles involve multimillion-dollar damages and occasionally attract media attention due to their public-safety implications. Yet his focus remains constant: securing justice for people whose lives have been permanently changed by negligence.

Comprehensive Advocacy From Trial through Judgment

Appellate advocacy requires a different kind of precision than trial work. It centers on mastering the record and presenting persuasive arguments before higher courts.

As a San Jose injury appeals lawyer, Mark O’Connor manages every aspect of the appellate process—from issue development and briefing to oral argument before higher courts. His appellate skill reinforces Shea & Shea’s reputation as a firm capable of seeing complex litigation through to its conclusion, no matter how far the case travels within the judicial system.

Career Background and Experience

Before joining Shea & Shea, Mark B. O’Connor spent fifteen years as a partner with Clapp, Moroney, Bellagamba & Vucinich, a prominent Bay Area defense firm. From 1986 to 2001, he represented insurance companies and their insureds in civil litigation matters ranging from automobile and premises liability to products liability and bad-faith suits.

This extensive insurance litigation experience gives Mr. O’Connor a rare dual perspective. He understands the strategies and valuation models insurance carriers use when evaluating injury claims, as well as the tactics defense counsel employ to minimize exposure. That insider knowledge helps injured clients by anticipating defense moves and strengthening negotiations.

When he joined Shea & Shea in 2001 as a personal injury attorney, Mr. O’Connor redirected his career toward representing plaintiffs exclusively. Since then, he has applied his years of experience and defense-side insight to achieve significant verdicts and settlements for clients facing the most severe injuries.

Representative Cases and Results

Throughout his career, Mark B. O’Connor has handled many catastrophic personal injury cases with statewide impact. Representative examples include:

• Kathleen O’Donnell v. Conway, Inc., Tonya Fortier and Katherine Kao ($9.28 Million Verdict) – Co-trial counsel with Michael M. Shea Jr. Jury found the trucking company 50 percent liable after a tractor-trailer failed to allow a safe merge, causing a catastrophic rollover. The plaintiff sustained multiple toe amputations and underwent six surgeries.
• City of Morgan Hill v. Ernest C. Brown – Appellate advocacy involving governmental liability and roadway design.
• McCormack v. Pacific Gas & Electric Company – Litigation addressing utility-company negligence and public-safety obligations.

These and other outcomes demonstrate his ability to manage cases that blend detailed technical analysis with powerful human stories—an essential combination in catastrophic-injury law.

Honors and Professional Memberships

Mark B. O’Connor’s dedication to his clients and the profession has been recognized repeatedly. He has earned Super Lawyers attorney recognition every year from 2007–2015 and again from 2017–2025.

Aside from being an active Western Trial Lawyers Association member. Mr. O’Connor participates in several professional organizations that promote continuing education and ethical advocacy, including:

• Santa Clara County Bar Association
• Consumer Attorneys of California
• American Association for Justice

These affiliations reflect both peer recognition and an ongoing commitment to improving the quality of trial practice in California.

Bar Admissions and Education

• State Bar of California, 1986
• S. District Court – Northern District of California
• S. Court of Appeals – Ninth Circuit

Education

• D., Santa Clara University School of Law, 1986
• A., Marquette University, 1982

A Record of Excellence

Over nearly forty years of practice, Mark B. O’Connor has combined technical mastery with genuine compassion for the people he serves. His dual background—first defending insurance carriers, now holding them accountable—allows him to view every case from both sides of the table. That insight, along with his command of California personal injury appeals, makes him an invaluable part of Shea & Shea’s trial and appellate team.

Clients seeking a traumatic brain injury attorney, counsel for spinal cord injury lawsuits, or representation in complex post-trial proceedings will find Mr. O’Connor a steadfast advocate and a seasoned guide through the most challenging phases of litigation.

Past Employment Positions

• Clapp, Moroney, Bellagamba and Vucinich, Partner

Contact Shea & Shea

If you or someone you love has been seriously injured, contact Shea & Shea at (408) 292-2434 for a free consultation with an experienced San Jose injury appeals lawyer.