Vice squad cops were waiting for Bill Baird that day and he knew it.
When he showed contraceptive devices to 2,500 Boston University students, Baird did it hoping he would leave the lecture in handcuffs.
The 79-year-old re-created the story last week for a much smaller audience, on the eve of the 45th anniversary of his arrest.
He told about a dozen Democrats inside a stately home across the Charles River how Boston police helped advance his plan that day.
How his April 1967 arrest for giving spermicidal foam to an unmarried 19-year-old coed set up a constitutional challenge that propelled his case to the U.S. Supreme Court, which resulted in the court's decision that gave unmarried people the same rights to birth control as married people.
But he also described how that decision, and others since then, also came at a personal price.
Decades of activism for birth control and abortion rights cost him a marriage, and the trust of most of his children, Baird said. It also left him with barely enough income to get by.
The lecturer who once netted $3,000 a speech said he poured the money into court cases, and running clinics that gave abortions to poor women.
Baird said he dodged bullets. Survived a firebombing at one of his suburban New York abortion clinics. Endured death threats along the way.
"My mail runs a hundred to one: people praying for my death," he said.
Baird told the audience he believes opposing political and religious forces are threatening the causes of privacy and freedom he's championed.
In 1979, his name was on a different Supreme Court decision that gave minors the right to abortions without parental consent.
But as a recent cancer survivor, Baird said he also thinks about his mortality. He said he fears that when he's gone, his life's work will be forgotten.
"I say tonight, `Will you help me?' `Will you write a letter?' `Will you get me a speaking engagement?'"
Baird says some people have called him a baby murderer and the devil because of his pro-abortion work.
His crusade started in 1963, when a woman who tried to give herself an abortion with a coat hanger died in his arms in a New York City hospital. He was clinical director for a contraception company at the time.
Baird says he opened the country's first abortion counseling center a year later. The facility on Long Island, N.Y., referred women to physicians who would perform then-illegal abortions. In decades that followed, Baird operated two clinics on Long Island and another in Boston where women could go for legal abortions.
He often pitted himself against Catholic Church leaders who preached an anti-abortion message.
In 1979, he sued to try to stop a public church service by Pope John Paul II in Boston. In 1985, a Catholic bishop led 3,000 people in a protest at one of Baird's New York clinics.
Baird also claims some feminists and pro-choice forces have tried to discredit him or downplay his contributions. He carries around a copy of a pamphlet he says shows that unlike him, Planned Parenthood opposed abortion in the early 1960s.
But both supporters and some who have opposed him said last week that Baird already has a place in history.
The Rev. Frank Pavone, the Catholic priest who heads the anti-abortion organization Priests for Life, said he respects Baird as a "warrior."
Pavone said the two became friends after years of meeting at Right to Life conventions, where Baird pickets each year. In the past, the two men released a joint statement asking their supporters to avoid inflaming the other side with rhetoric.
"Many people who come to know him well draw strength from his fighting spirit," said Pavone. "... If you can break the law peacefully to advance a cause, both he and I believe in that."
Officials from Planned Parenthood Federation of America in New York declined an interview about Baird last week, but said in a statement that his 1972 Supreme Court win was "a cultural landmark that has impacted generations of Americans."
Massachusetts lawyer Thomas Eisenstadt also called Baird a "trailblazer." He is the man whose name is on the other side of the 1972 decision, Eisenstadt vs. Baird, that gave unmarried people the right to birth control.
Then sheriff of Suffolk County in Massachusetts, Eisenstadt was Baird's jailer when the activist spent 36 days in Boston's old Charles Street Jail after the conviction that followed his Boston University arrest.
"That was preposterous, those old, arcane laws," Eisenstadt said of the case. "I think it's made a tremendous impact on society."
The former sheriff also said Baird had a knack for attracting publicity.
"As he was leaving the jail he said, `Stick with me Sheriff. You'll get a lot of TV coverage.'"
A couple hours before his Cambridge lecture last week, Baird went back to the old Charles Street Jail.
Squalid conditions prompted a judge to order the facility to close in 1973. It reopened as a luxury hotel in 2007.
Baird said his memories of rats and lice, of a blood-stained mattress, of screams echoing among the granite cells, still unnerve him.
While at the hotel, Baird studied an exhibit with his photo that describes him as one of the old jail's notable prisoners. Then he posed for photos by the bars of an old cell, when a stranger who walked by tried to joke with him.
Before Baird quipped he'd actually once been an inmate.
"Wow," the man said then, "There's a prisoner here."
Later, Baird's words also left an impression with the clot of Cambridge Democrats who listened to him speak for more than an hour.
"I have no money. I have no political power," Baird told them. "But I will never surrender. I will never give up. I believe that women and women alone must be free to make these choices."
There were no handcuffs this time when his lecture ended.