MOSCOW — About two weeks before he was shot and killed in the highest-profile political assassination in Russia in a decade, Boris Y. Nemtsov met with an old friend to discuss his latest research into what he said was dissembling and misdeeds in the Kremlin.

He was, as always, pugilistic and excited, saying he wanted to publish the research in a pamphlet to be called “Putin and the War,” about President Vladimir V. Putin and Russian involvement in the Ukraine conflict, recalled Yevgenia Albats, the editor of New Times magazine. Both knew the stakes.

Mr. Nemtsov, a former deputy prime minister, knew his work was dangerous but tried to convince her that, as a former high official in the Kremlin, he enjoyed immunity, Ms. Albats said.

“He was afraid of being killed,” Ms. Albats said. “And he was trying to convince himself, and me, they wouldn’t touch him because he was a member of the Russian government, a vice premier, and they wouldn’t want to create a precedent. Because as he said, one time the power will change hands in Russia again, and those who served Putin wouldn’t want to create this precedent.”