Related Clues:

• Provide a counter-example
• Not allow
• Make invalid
• Said three times, a liar's policy
• ''. . . which nobody can __!''
• Contravene
• Make ineffective
• Refuse to acknowledge
• Abnegate
• It's all three words of a liar's policy
• Refuse to accept
• One-third of a liar's policy
• Prove wrong
• Cast doubt upon
• Shoot down