Randolph Thrower’s mastery of federal tax law earned the Atlanta lawyer a presidential appointment to the commissioner of the Internal Revenue Service in 1969. His application of that knowledge made him a casualty during the Watergate scandal that roiled Washington in the 1970s.

Thrower refused to allow President Richard Nixon to use the IRS to punish his political enemies, an act that prompted his resignation and sent the lawyer back to private practice in 1971.

“He knew doing that would have compromised the (IRS) forever,” said Bill Bradley, senior partner at Sutherland Asbill & Brennan in New York City. “And that he had the courage to say ‘No!’ and understanding that the White House was going to be very displeased with him gives you a real understanding of the kind of person that he was and the kind of courage that he had.”

Patricia Barmeyer said her father was not afraid of criticism and was comfortable making potentially unpopular decisions, as long as they were correct ones.

“He had an unerring moral compass,” said his daughter, who lives in Atlanta. “He had an ability to help other people see the right thing to do.”

Thrower died Saturday at his Atlanta home of natural causes. He was 100.

A memorial service is planned for 11 a.m. Saturday at Northside United Methodist Church. H.M. Patterson & Son, Spring Hill Chapel was in charge of cremation arrangements.

Born in Tampa, Fla., Thrower came to Atlanta to attend Georgia Military Academy, now Woodward Academy. He went on to graduate from Emory College in 1934 and Emory’s law school in 1936, the same year he joined the law firm of Sutherland, Tuttle & Brennan.

In 1939 Thrower married the former Margaret Logan Munroe and the couple lived in New York and California before returning to Atlanta to settle down. They eventually had five children together and were married for 70 years before she died in 2009.

As an attorney, Thrower, a Marine Corps veteran, was a “fierce advocate” for his clients, Bradley said.

“He loved to present his client’s position, but he was always respectful of the other side,” he said.

“He set the bar for the bar,” said Sam Massell, president of the Buckhead Coalition and former mayor of Atlanta. “All Atlantans should be very proud of how he represented us in Washington and in judicial circles everywhere.”

Thrower actively practiced law until after his 89th birthday, but continued to advise and see some clients into his 90s, his daughter said.

In addition to his daughter, Thrower is survived by daughters Margaret MacCary and Laura Harris, both of New York City, and Mary Wickham of Richmond, Va.; son, Randy Thrower of Decatur; 11 grandchildren; and nine great-grandchildren.