Dante Mattioni, 83, of Chestnut Hill, a trial lawyer who operated his own firm in Philadelphia for 45 years, died May 5 of complications from congestive heart failure at the Hospice of Philadelphia-Falls center.

Mr. Mattioni founded his firm, Mattioni Ltd., in 1963, specializing in admiralty and maritime law based on his own experience as a Merchant Marine officer. He later expanded the firm to include business law, estate planning, real estate and labor law.

In 1965 he formed a partnership with two of his brothers, Faustino and John, and later added brothers Blasco and Eugene.

Mr. Mattioni also had served as a Philadelphia assistant district attorney and as a deputy attorney general for Pennsylvania. He served at the Pennsylvania Constitutional Convention in 1967 and was a member of the board of the Philadelphia Housing Authority in 1968.

Active in many professional, charitable and civic organizations, he was chairman of the Chapel of Four Chaplains and served on the boards of the Philadelphia Historical Society of the U.S. District Court for the Eastern District of Pennsylvania, the Maritime Exchange for the Delaware River and Bay, the Ports of Philadelphia Maritime Society and the Malvern Institute.

For his community service, Mr. Mattioni was named a Cavalier of the Republic of Italy and Man of the Year by the Maritime Society of Philadelphia.

A Philadelphia native, he was a graduate of South Philadelphia High School and Kings Point U.S. Merchant Marine Academy. He received a master mariner’s license and served as a Merchant Marine officer before earning a degree at Temple University School of Law.

He is survived by his wife, Susan; a daughter, Jennifer; five sisters and two brothers. Two brothers preceded him in death.

A memorial service was held May 10 at St. Paul’s Episcopal Church in Chestnut Hill. Memorial donations may be made to the Wounded Warrior Project at www.woundedwarriorproject.org. – WF