In mid-career, Harvard-educated tax attorney Paul Zerby left his job at a prestigious Minneapolis law firm to try something new.

He wanted to use his legal training to help people — and not just wealthy clients.

Zerby taught at the University of Minnesota Law School, then took a job as assistant attorney general for the state of Minnesota, where he worked for the next 25 years on a wide variety of cases.

His son Paul Zerby Jr., of Minneapolis, remembers his dad’s “relentless pursuit” of the Reserve Mining case, the landmark environmental litigation that resulted in the company being held responsible for dumping taconite tailings in Lake Superior and contaminating drinking water. “He went after that with a vengeance.”

After Zerby retired from the Attorney General’s Office in 1998, he lent his services to Minnesota Advocates for Human Rights, working on Liberian immigration cases.

In his late 60s, Zerby embraced a new challenge: running for and winning election to the Minneapolis City Council.

“He really and truly liked people,” said his wife, Elizabeth. “That’s why politics appealed to him. He knocked on every door in the Second Ward. He thought if he wanted people to vote for him, he should ask for their vote.”

As a councilman, Zerby was a good listener, said his aide Greg Simbeck. “He had a lightning-fast brain and a passion for helping people. He was the quintessential citizen servant.”

Zerby, 86, died on Jan. 5 of congestive heart failure and Parkinson’s disease.

Born in Fargo, Zerby used to joke that his childhood was so tough that he walked a mile to and from school — uphill both ways.

When he was 10, Zerby’s family moved to Duluth and later to St. Paul, where he attended what was then Cretin High School. He graduated from the University of Minnesota, then served in the U.S. Army in Oklahoma and South Korea before marrying Elizabeth in 1955.

After graduating from Harvard Law School, Zerby clerked for a judge in New Hampshire, then returned to Minnesota to practice at the firm now called Dorsey & Whitney for 13 years before moving to the public sector.

Zerby was proud of his public service and the things he was able to accomplish on the City Council, according to Elizabeth. He helped establish a Citizens Review Board to handle police-community relations — “so there would be a place for people with complaints to go and be heard.”

The city’s smoking ban was his top accomplishment, according to Zerby, who co-authored the ordinance. “I really believe we will actually save some lives and make some lives better,” he told the Journal near the end of his term.

During his final year on the council, Zerby also authored a living-wage ordinance. “It was his crowning achievement,” said Simbeck.

Zerby served on the council from 2002 to 2006. “He would have run for a second term but I refused to be his campaign manager again,” said Elizabeth.

Retirement gave Zerby time to complete and publish his novel, “The Grass,” a fictional account of a young soldier during the Korean War. “It was pretty racy,” said Elizabeth.

In his final years, “Parkinson’s disease reduced his world, but he always managed to keep a little sense of humor,” said Paul Jr. “He handled his decline with a lot of grace and dignity.”

A memorial service will be held from 2 to 4 p.m. Jan. 25 at Walker Place, 3701 S. Bryant Av., Minneapolis.

In addition to his wife and his son, Zerby is survived by sons Steven of New York and Matthew of Minneapolis; daughter Anne of White Bear Lake; brother D. Michael Zerby of Fridley; sister Susan Shelby of Chicago, and five grandchildren.