The paper based on V.I. Lenin’s works, published in sources and special historical materials, explores the true meaning and content of Lenin’s letter dated February 20, 1922 to the People’s Commissar of Justice of the RSFSR D.I. Kursky. This secret letter intended to modernize Soviet legal policy under the conditions of the NEP. Lenin wanted to direct the efforts of the People's Commissariat of Justice (Narkomyust) to fight the enemies of Soviet power. In carrying out this modernization of legal policy V.I. Lenin relied on the qualified Soviet lawyer D.I. Kursky, who for ten years (1918–1928) remained the permanent People's Commissar of Justice of the RSFSR, and then the USSR. In 1922, Lenin, in a secret letter, saw the Socialist Revolutionaries and Mensheviks as the main enemies in the transformation of Russia. One of them was a prominent Russian historian, a former Bolshevik fellow-fighter who went over to the Mensheviks, N.A. Rozhkov. Renegades apostates like him aroused special hatred in Vladimir Ilyich. V.I. Lenin pursued Nikolai Alexandrovich Rozhkov until his last breath. It should be noted that the addressee of the letter D.I. Kursky generally successfully implemented Lenin's demands and instructions for modernization and justice during the NEP years. He practically created a new Soviet law, but in 1928 I.V. Stalin began to sharply curtail the NEP, and D.I. Kursky was “diplomatically” sent by the USSR plenipotentiary envoy to Italy.