Historical clue formulations

• Thwart the interrogators — 2023-05-07
• Stop responding — 2021-07-31
• Refuse to talk — 2021-05-21
• Hush one's mouth — 2019-03-23
• Stop talking — 2014-11-18
• Zip one's lip — 2007-07-02
• Refuse to talk — 2001-06-25
• Stop talking — 1999-06-24
• Button one's lip — 1994-01-30