What separated the Soviet Union and Russia from the West, she said, were not enlightened leaders but systems of checks and balances. With the Helsinki Group, for example, she tried to monitor the authorities in the Soviet Union by holding them to their own stated commitments to human rights.

Her views were also a critique of the vilification of Mr. Putin as personally responsible for rolling back Russian democracy and the idea, sometimes heard among his opponents, that if he were to step down Russia might be ruled differently. Only by building civil society could Russians achieve better results from their leaders, she maintained.

“She kept pushing that point,” Ms. Lokshina of Human Rights Watch said. “There could be different leaders, but if there is a healthy system of checks and balances, it is much more difficult to do serious damage. Unfortunately, in Russia, that is not the case.”

She is survived by two sons, five grandchildren and three great-grandchildren.

Born in Crimea on July 20, 1927, Ms. Alexeyeva became a dissident as a member of what she called the “thaw generation” under the Soviet leader Nikita S. Khrushchev, who introduced a period of relaxed censorship.

When the screws tightened again in Leonid Brezhnev’s Soviet Union, she and other Moscow intellectuals risked their lives to keep pressing for freedom and human rights. Ms. Alexeyeva typed a samizdat journal, called the Chronicle of Current Events.

She and other dissidents saw an opening when the Soviet Union signed a treaty in Helsinki that required it to uphold certain rights at home, though apparently it had little intention of doing so. In 1976, she co-founded the Helsinki Group to monitor compliance.