When Roju (Shogun's Council of Elders) Masayoshi HOTTA visited Kyoto to ask for Imperial sanction to sign the Japan-US Treaty of Amity and Commerce in 1858, Shigetoku stood against the move together with Tomomi IWAKURA, but both were suspended because of the protest.
安政5年（1858年）には日米修好通商条約の調印のための勅許を求めて老中堀田正睦が上洛すると、岩倉具視らと反対して謹慎させられる。