Timothy Lui-Kwan, a veteran Honolulu attorney who defended the University of Hawaii at Hilo over the Thirty Meter Telescope project, died after lifeguards found him floating unconscious in waters off Kaimana Beach in Waikiki on Sunday. He was 66.

Police said Lui-Kwan was swimming with his family at midday and was later found unresponsive. Lifeguards brought him to shore and administered cardiopulmonary resuscitation before he was transported in a critical condition to a hospital and later died.

Lui-Kwan was a partner in the Honolulu law office of Carlsmith Ball. He focused on administrative law and represented a range of clients in proceedings before regulatory agencies and boards, including UH Hilo regarding the $1.4 billion TMT project since 2008.

He was a member of UH Hilo’s defense team in both the first contested case hearing five years ago and the latest replay hearing, which has yet to wrap up.

Born in Hilo, Lui-Kwan was one of 10 siblings in a family that moved to Honolulu while he was in high school. He graduated from Kamehameha Schools.

Lui-Kwan worked as an archaeologist for the Bishop Museum while earning his anthropology under-graduate degree at the University of Hawaii at Manoa. He also worked there while attending UH’s law school.

Before joining Carlsmith Ball in 1989, Lui-Kwan worked for the Legal Aid Society of Hawaii on the Big Island and then served as deputy planning director and a deputy corporation counsel for the County of Hawaii.

As head of the Hawaii State Bar Association Senior Counsel Division, he established a program that sent lawyers to rural communities for free legal clinics.

“He was an unbelievably caring person,” said his older brother, Ivan Lui-Kwan, also an attorney. “I relied on him a lot. He was a person who was so giving, it was unbelievable.”

Greg Lui-Kwan, another sibling who is also an attorney, said his brother went out of his way to help people.

“It’s hard to think of a life without my brother. The loss to our family is monstrous,” he said.

Carlsmith Ball Chairman Karl Kobayashi said in a statement: “We are deeply saddened by the loss of our friend and beloved colleague, Tim Lui-Kwan and we extend our heartfelt condolences to his family. Tim was an excellent attorney who was passionate about his work, particularly in the area of historic preservation. His passing is a tremendous loss to all of us at Carlsmith Ball, but his legacy and spirit of aloha will continue through the attorneys he mentored, the clients with whom he worked and the many members of the community whom he cared for and generously assisted.”

UH offered this statement: “The University of Hawai‘i extends its heartfelt condolences to the Lui-Kwan ‘ohana. Tim’s special gifts and many talents, his humble sense of humor and of place, and his wise counsel will be sorely missed.”

In an interview with the Hawaii State Bar Association’s online “Family Connections” feature, Lui-Kwan said one of the tenets of his law practice was to treat others as you want them to treat you.

“Hawaii is too small — you never know when the shoe will be on the other foot, and the chance of repeat encounters with the same parties and the same attorneys are extremely high,” he said.

He is survived by wife Lin Lei “Marty” Martinson, daughters Erica Mahina Lui-Kwan and Malia Paul, and son Nicholas.