In 1937 Spiridonova was arrested yet again, with several former party comrades including her husband, her teenaged stepson, her invalid father-in-law, Alexandra Izmailovich, Irina Kakhovskaya and the latter's aged aunt. The group was accused of plotting to create a united counter-revolutionary center and to assassinate Bashkir Communist leaders. Spiridonova underwent cruel interrogation in prison in Ufa and in Moscow for several months, without admitting any guilt, although a confession was extorted from her husband. In November 1937 she wrote a long letter to the 4th Section of the Main Directorate of State Security (GUGB) within the People's Commissariat for Internal Affairs (NKVD) from her cell, protesting against the prison treatment inflicted on her, contesting the correctness of the judicial procedure and rejecting every single charge. The letter proclaimed that she fully supported the construction of socialism and acknowledged the Communist leadership. However, she concluded what was later called her 'last testament' with a vibrant heart-felt plea against capital punishment, twice abolished in the aftermaths of the February and October Revolutions and twice re-established by subsequent governments despite vehement protests from the Left Social-Revolutionaries: