Samuel J. Stoller

Area of Emphasis Matthew Moses is a shareholder in Babst Calland’s Corporate and Commercial Group and is a member of, and past co-chair of, its Energy and Natural Resources Group. Mr. Moses’ practice includes business structuring and governance; mergers, acquisitions and divestitures, particularly dealing with environmentally-challenged assets; real estate transactions and development; information technology; and routine and complex commercial contracts in (among other areas) proc...

Irv currently serves as the firm's Managing Shareholder. He concentrates his practice on land use, zoning , and real estate litigation. Prior to joining Tucker Arensberg, he served as in-house counsel to the Housing Authority of the City of Pittsburgh. He has represented land owners and developers before planning commissions, zoning hearing boards, governing bodies, administrative agencies, and the Court of Common Pleas. In addition, Irv serves as counsel to numerous food service and restaura...

Katelyn O'Connor is a top attorney recognized by Best Lawyers in the practice area(s) of Litigation - Labor and Employment. Katelyn, who practices law in Pittsburgh, Pennsylvania, has been recognized since 2026. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Katelyn is held by other top lawyers in the same geographic and legal practice area.

Jackie represents a variety of employers, including manufacturing and industrial companies, television stations, hospitals, and universities, in both federal and state courts as well as before government agencies such as the Equal Employment Opportunity Commission, the Office of Federal Contract Compliance Programs, the National Labor Relations Board, and numerous state and local human rights commissions. Her practice includes advice on affirmative action, union avoidance, reasonable accommod...

William D. Clifford is a top attorney recognized by Best Lawyers in the practice area(s) of Commercial Litigation, Construction Law and Litigation - Construction. William D., who practices law in Pittsburgh, Pennsylvania, has been recognized since 2006. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which William D. is held by other top lawyers in the same geographic and legal practice area.

Area of Emphasis Jean Mosites is of counsel in the Environmental, Energy and Natural Resources, and the Public Sector groups of Babst Calland. She is past co-chair of the Environmental Group. Her practice includes client counseling on environmental compliance in the energy sector, resolving liabilities under federal and state remediation programs, as well as administrative appeals and environmental litigation in state and federal courts. Ms. Mosites represents clients in the Pennsylvania Comm...

David has tried numerous cases in both state and federal courts and has argued in the U.S. Courts of Appeals on multiple occasions. From 2000 to July 2005, David left private practice to serve as an Assistant United States Attorney in the Office of the United States Attorney for the Southern District of New York. There he handled a variety of criminal prosecutions and investigations and worked closely with representatives of financial institutions, including internal auditors, compliance offi...

Ronald J. Brown is a top attorney recognized by Best Lawyers in the practice area(s) of Municipal Law. Ronald J., who practices law in Pittsburgh, Pennsylvania, has been recognized since 2019. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Ronald J. is held by other top lawyers in the same geographic and legal practice area.

Mr. O’Connor has been a member of the firm for 20 years. His practice is devoted to the representation of physicians and hospitals in medical malpractice cases. Brian also represents health care providers in litigation before the Pennsylvania State Board of Medicine. Mr. O’Connor has tried over 45 jury trials on behalf of physicians and hospitals throughout the counties of Western Pennsylvania and the Federal District Court in Pittsburgh and Erie. Mr. O’Connor has participat...

Maureen Kowalski is a top attorney recognized by Best Lawyers in the practice area(s) of Workers' Compensation Law - Employers. Maureen, who practices law in Pittsburgh, Pennsylvania, has been recognized since 2006. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Maureen is held by other top lawyers in the same geographic and legal practice area.