By Adam Clymer

New York Times News Service

Birch Bayh, the liberal former senator from Indiana whose work in Congress had an enduring impact on American life — in protecting women from sex discrimination in education, guaranteeing 18-year-olds the right to vote and providing for the removal of a sitting president — died Thursday at his home in Easton, Maryland. He was 91.

The cause was pneumonia, the family said.

Bayh, a Democrat who served in the Senate from 1963 to 1981, drove some of the most historic legislation of his era. He was the principal architect of two constitutional amendments: the 25th, which dealt with presidential disability and vice-presidential vacancies, and the 26th, which gave 18-year-olds the vote in state and federal elections.

He was a chief Senate sponsor of the failed Equal Rights Amendment, which would enshrine in the Constitution protections against discrimination on the basis of sex. He pushed through another amendment that would have abolished the Electoral College and had presidents elected by direct popular vote, lining up strong support in the Senate but failing in the end to muster enough votes to send it to the states for ratification.

And he championed Title IX, drafting the language for that landmark federal legislation, which barred sex discrimination at schools and colleges and greatly expanded sports programs for women.

“I’d say probably this had a more profound impact on more Americans than anything else I was able to do,” he said in a telephone interview for this obituary in 2010.

Title IX, an amendment to education legislation passed in the 1960s as part of President Lyndon B. Johnson’s Great Society programs, was developed while Congress was considering the Equal Rights Amendment.

Billie Jean King, the former tennis star and a strong advocate for women’s equality in sports, said in a statement, “You simply cannot look at the evolution of equality in our nation without acknowledging the contributions and the commitment Sen. Bayh made to securing equal rights and opportunities for every American.”

Lines of succession

His first successful amendment, the 25th, emerged after President John F. Kennedy was assassinated in 1963, and Johnson, then the vice president, succeeded him to the White House. The transition left no sitting vice president, and the next two in line of succession were the speaker of the House, John W. McCormack, who was 71, and the Senate president pro tempore, Carl Hayden, who was 86.

In 1964, the Senate passed an amendment put forth by Bayh permitting a president to nominate a new vice president if that office became vacant (as happened with Johnson’s succession). But the House, led by McCormack, would not consider the measure while he remained next in line.

Then, in 1965, after Johnson had been elected and Hubert H. Humphrey had become vice president, both chambers passed the amendment.

Besides clarifying the line of succession and giving the president the power to nominate a new vice president, the measure spelled out the process by which the vice president would be named acting president if the president was unable to perform his or her official duties. It also detailed how disputes about a president’s ability to discharge official powers would be resolved.

The amendment was ratified by the states in 1967. It was first put to use in 1973, when Spiro Agnew resigned as vice president and was succeeded by Gerald Ford. It was invoked again in 1974, when President Richard Nixon resigned and Ford succeeded him. Ford chose Nelson Rockefeller as vice president

Plane crash in the fog

Perhaps the most dramatic moment in Bayh’s life took place away from the Senate. He was traveling with his friend, Sen. Edward Kennedy of Massachusetts, to a Democratic convention there June 19, 1964. Bayh was scheduled to be the keynote speaker, and Kennedy was to be nominated for his first full term. Kennedy had entered the Senate through a special election to fill the seat left vacant when his brother John became president.

After voting for final passage of the 1964 Civil Rights Act, the two senators rushed to National Airport, where a small chartered plane was ready to take them to Westfield, Massachusetts. But the airport in Massachusetts was fogged in, and the plane crashed when the pilot tried to make an instrument landing.

The pilot and a Kennedy aide were killed, and Kennedy’s back was broken. Bayh and his wife, Marvella, were shaken up but managed to climb out of the crashed plane. But fearing a fire from aviation fuel, Birch Bayh went back to the plane and dragged Kennedy to safety through a hole in the fuselage.

He is survived by a son from that marriage, Birch Evans Bayh III, a former governor of Indiana and senator from that state who is known as Evan; and two grandchildren. He is also survived by his second wife, Katherine (Halpin) Bayh, known as Kitty, and their son, Christopher.