This article analyzes historical sources devoted to the “Beria case”, in which it is suggested that the true version of the arrest and execution of L. P. Beria is far from the official one. They also give opinions that the so-called “Beria’s letters from imprisonment” are fakes created to con-ceal the truth about extrajudicial reprisal against this prominent figure of the CPSU and the Soviet government. The study of the materials of the investigative case and historical and liter-ary sources made it possible to formulate a hypothesis that these documents were written after the death of L. P. Beria alone by his regular speechwriter V. N. Merkulov or a group of authors, which included Merkulov, also a victim of repression. To carry out an authorship examina-tion of Beria’s letters to the CPSU Central Committee, a text attribution method was applied based on the measure Burrows’s Delta with Eder’s Delta and Cosine-Delta modifications, and Ward’s clustering algorithms allowed visualization of solutions in the form of dendrograms. As a result, it is shown that the intellectual authorship of the documents under investigation, which date back to the period between June 28 and July 2, 1953, belongs to speechwriters who previously took part in writing the texts of Beria’s public speeches, including V. N. Merkulov, who is very likely the main author of these texts. Merkulov, both by his own admission and by the confession of L. P. Beria himself, beginning in the 1930s, was the author of the texts of his public speeches and official documents, since Beria himself had a poor command of the written form of the Russian language.