How did Maxim Gorky’s death become part of the 1938 trial of Nikolay Bukharin and other defendants?

During the 1938 show trial of Nikolay Bukharin and other defendants, the prosecution alleged that Maxim Gorky had been the victim of an anti-Soviet plot orchestrated by the "Bloc of Rightists and Trotskyites."1

The former secret police chief Genrikh Yagoda, who was a defendant in the trial, confessed to ordering three doctors to murder Gorky, as well as other prominent figures such as V.R. Menzhinsky and V.V. Kuibyshev. These accusations were part of a broader, fabricated narrative used by the Soviet Union during the Great Purge to eliminate political rivals of Joseph Stalin. While the official Soviet account claimed Gorky was murdered by this conspiracy, some Western authorities have suggested that Stalin himself may have ordered Gorky’s death due to the writer's growing disillusionment with the regime. It is now established that the evidence and confessions presented during these trials were coerced through torture and intimidation.12