Related Clues:

• Certify (to)
• Bear witness (to)
• Warrant, with 'to'
• Show to be so
• Give evidence - sounds a trial
• Certify or bear witness
• Give evidence, bear witness
• Assert, state as fact
• Declare to be true or genuine
• Declare to be true, bear witness
• State as fact, assert
• Demonstrate beyond doubt
• Demonstrate to be true
• Assert, avow
• State as a fact, assert