Thomas Hale Boggs Jr, the long-term chairman of legacy Patton Boggs, and most recently chairman emeritus of newly merged Squire Patton Boggs, has died unexpectedly at his Maryland home.

Boggs, 73, was one of Washington DC's most influential lobbyists and public policy lawyers. He served as chairman of the executive committee of Patton Boggs, prior to its merger earlier this year with Squire Sanders.

He joined what became Patton Boggs in 1966 shortly after the firm was founded, where he advised on a broad range of legislative and regulatory matters including tax, health care, trade and telecommunications.

In June, he oversaw the passing of the leadership of the firm's public policy committee to practice co-chairs and former US senators Trent Lott and John Breaux. At the time, Boggs said: "I am energized by the strengths we have brought together in this combination, and have no thought of slowing down."

Squire Patton Boggs vice chairman Don Moorehead said Boggs' "monument is and will remain the law firm he built and guided into a Washington powerhouse and then into a combination that resulted in one of the world's preeminent law firms".

"This is obviously a very sad day for our firm, the Boggs family and all of those who, as I did, called Tom a friend and a colleague," added Moorehead. "He was a one-of-a-kind individual who pioneered the now widely imitated combination of law and public policy and played key roles in shaping the policy and political agenda for decades."

"More than that, he was that rare combination of a creative leader (is there a Steve Jobs of law firms?) who inspired all of us and a great friend to whom no personal matter was too trivial to discuss and resolve.

"He was to all of us, the best of friends and to those of us who have spent much of our professional careers as his partner, he remains, and will remain, one of the larger than life figures who never lost his humanity."