After conviction for contempt of Congress, he was blacklisted, and in 1950, spent 11 months in prison in the federal penitentiary in Ashland, Kentucky.
After conviction for contempt of Congress, he and the others were blacklisted from working in Hollywood. In 1950, Dalton served 11 months in prison as punishment for the contempt conviction, in the federal penitentiary in Ashland, Kentucky.