His concerns about Chernobyl were one reason he sought a seat in the Congress of People’s Deputies, a body Mr. Gorbachev created in 1989; he was elected to Parliament the following year. After the August 1991 coup attempt, some parliamentary leaders were forced out, and Mr. Shushkevich was named the body’s chairman.
After he was ousted by Mr. Lukashenko in 1994, Mr. Shushkevich became a vocal critic of his successor, and of Mr. Lukashenko’s penchant for making pie-in-the-sky promises.
“If he can do it all, he is Moses,” Mr. Shushkevich told The Times in July 1994. “But he is not. Solzhenitsyn said that Vladimir Zhirinovsky” — a firebrand ultranationalist in Russia — “was the caricature of a Russian patriot. Well, Lukashenko is the caricature of Zhirinovsky.”
Mr. Lukashenko, though, may have exacted a measure of revenge. The Times reported in 2002 that in 1997, he issued an executive decree setting new rates and cost-of-living conditions for pensions of state officials — except for former chairmen of the Supreme Soviet, a club that consisted of Mr. Shushkevich and one other man. In hyperinflation-prone Belarus, that hit Mr. Shushkevich hard in the pocketbook.
His monthly payment “used to be around $200,” Mr. Shushkevich told The Times, “which is a good pension by our standards.”
“Now,” he said, “it is 3,196 rubles. That equals $1.80.”
In addition to his wife, his survivors include a son, Stanislau, and a daughter, Alena.
Mr. Shushkevich continued to fire away at his successor to the end. In one of his last interviews, in December, he linked Mr. Lukashenko and Russia’s president, Vladimir V. Putin.
“Putin and Lukashenko are still unhappy with the fall of the U.S.S.R.,” he was quoted as saying. “They want to rule forever. This is not the way to create a democracy.”