Enclosed in their 1961 tax return forms, Americans found a letter.

The short note to taxpayers was written by the new Internal Revenue Commissioner. With this personal touch, Mortimer Caplin hoped to convince Americans of the virtues of tax collection. He wrote earnestly: “taxes are necessary for the kind of orderly government which will preserve America and its way of life.”

Those decades ago, The Washington Post called it “a touching little acknowledgement of the service that citizens perform by paying their taxes …  even if it is unlikely to reconcile taxpayers either to taxes or the tax collector.”

But Caplin had always been an optimist. He had ambitious ideas for simplifying the tax code, he was the first to computerize tax returns, and was the only IRS Commissioner to get a president to visit the building — not exactly the place a politician seeks a photo-op.

“We changed the philosophy,” Caplin said in an interview. “We encouraged our agents and personnel to be more friendly with the public. My feeling was we want to be helpful … to make people feel like someone wasn’t standing over them with a stick.”

Caplin’s approach to perhaps the most thankless, if not reviled, job in Washington is emblematic of a lifetime spent in the service of others and to meeting personal challenges. He has been a college boxer, a judge’s clerk, a World War II hero, a law professor, President John F. Kennedy’s IRS commissioner, the founder of a boutique law firm, a philanthropist, a husband and a father.

He turns 100 on Monday; a remarkable life celebrated in a touching 30-minute documentary produced by his Washington law firm, Caplin & Drysdale, ahead of his birthday.

Caplin is part of a quintessentially-Washington cadre of formerly high-profile public servants now quietly living in retirement here.  He is also among the last of the revered Greatest Generation. And like so many of those men and women born in the years just before the Great Depression, Caplin measures a good life by the strength of family and public service.

At an early birthday party at his law firm on Thursday afternoon, the men and women in attendance wore bright teal bowties – Caplin’s signature fashion accessory – in his honor. “He is a legend at the IRS,” John Koskinen, the current IRS Commissioner, said in remarks. “You mention Mort Caplin and even the youngest employees know who he is.”

Shelley L. Bishop (nee Davis), the first and only historian for the IRS, wrote a scathing tell-all book about IRS practices after she left the job in 1995. But when asked about Caplin in an interview, she said he reminded her there were good people in government.

“The most important point is that Mr. Caplin truly was a public servant and he viewed his work as an important issue of public trust and he took it seriously and I’m not sure we have a lot of that today,” she said. “At least Mr. Caplin gave it his best shot during those years. His has been a life very well lived.”

‘I was always running.’

The first Jewish law professor at the University of Virginia, Caplin had both Robert and Ted Kennedy as students, but it wasn’t through them that he first met the young Democratic senator from Massachusetts.

Caplin practiced law with a local Charlottesville lawyer, Bill Battle, who was in the same PT boat unit as John F. Kennedy during World War II. Battle, who would go on to be Kennedy’s ambassador to Australia, hosted an intimate get-together when Kennedy came through town in 1958 to speak at the law school.

The Kennedys had just returned from Florida, and Caplin remembers the would-be president was tan and lean and his wife, Jackie, was “as pretty as could be.”

“You had to be somewhat overwhelmed,” he said of that first meeting.

Caplin was introduced to Kennedy as an expert in tax policy. The ever-charming politician asked to read Caplin’s policy recommendations.

Caplin didn’t know that this brief encounter would change the course of his life.

Caplin grew up modestly on the Lower East Side of Manhattan, the grandson of eastern European immigrants. He came from a family of fighters, literally. His uncle managed champion boxers and Caplin, an avid swimmer, (until a few months ago he was still swimming almost daily and plans to take it back up this summer) would go on to box too at the collegiate level.

Caplin was on the cover of Time magazine in 1963. In that profile, he said of his ambition, “There may be something in being a member of a minority that makes a man run. … I was always running.” A UVA classmate said Caplin came to college determined to be first in his class and no one “had the energy to compete with him.”

When Kennedy won the White House in 1960, he tapped his brothers’ former professor to run the IRS. Several years into his administration, Kennedy sent a package of tax proposals to Congress that closely mirrored those earlier recommendations from Caplin, according to Time.

Reflecting on those days in government, Caplin recalls his favorite day as when he convinced the White House to have Kennedy stop by to address a gathering of regional IRS officials in Washington in April 1961. Kennedy agreed, and a plaque commemorating that day still hangs in the IRS building.

“You have just participated in a historic occasion,” Caplin told the crowd that day. “This is the first time in the history of our nation that a president of the United States has visited the Internal Revenue Service.”

That remains true to this day, an IRS official confirmed.

At the 2:30 mark you can see Caplin, in a bowtie and Buddy Holly-style glasses, introduce Kennedy, and his closing remarks around 6:10:

“Those were very special days,” Caplin said wistfully one recent afternoon, as if, just for a moment, he was transported back to 1961.

‘A life lived with gusto’

Caplin sat on a wingback chair inside his Chevy Chase penthouse apartment last week. Coffee was pre-poured into china teacups awaiting his visitors. Interspersed with the original art and the antique furniture were his real treasures: Photos of his family. And in a hallway outside of his bedroom an entire wall is filled with decades of framed memories.

His wife, Ruth, of 71 years, died in 2014. They’d met as counselors at a summer camp. He served as lifeguard, perched on a seat watching the kids play in the lake. But he said he couldn’t take his eyes off of Ruth.

“It was a pretty classic wonderful romance,” their son, Michael Caplin, 65, of Tysons. “It was an exquisite partnership and with genuine mutual respect and limitless consideration of the feelings of one another. There wasn’t a time when he wasn’t all for Ruth and she wasn’t all for him.”

Asked to describe his father in one story, Michael Caplin recalled about 20 years ago when his father was complaining of chest pains. They were in the elevator to rush him to the hospital, when they were joined by a couple Mortimer Caplin didn’t recognize from the building. They’d just moved from Iran, and Caplin stopped to ask them about themselves, welcome them to the neighborhood and offer his advice on favorite places in the area.

“Even in this time of medical alert he stopped to tune into the needs of others. It was an exquisite example of his priorities,” Michael Caplin said. “He does it humbly; he is without ego; he just does it because that is who he is. It’s a life lived with gusto.”

Theater enthusiasts, Caplin co-produced a Broadway show, “Execution of Justice” in 1986. His wife wrote a screenplay, “Mrs. Palfrey at the Claremont” that their oldest son, Lee, a Hollywood producer, had made into a movie when she was 85 years old.

The Caplins donated $4 million toward the creation of the 300-seat Ruth Caplin Theatre on UVA’s campus in 2013. Their daughter, Cate Caplin, is a theatrical producer and choreographer who lives in Los Angeles. But Friday, Caplin is bringing one of her shows east to be performed in the theater named for her mother and in time to celebrate her father’s 100th birthday with a toast in the lobby.

“It’s hard to believe; it’s a lot of years. I know a lot of people think about that — ‘Will I be 100, what’s it like?’ ” Mortimer Caplin said. “I try not to focus too much on it. You do the best you can.”

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