Possible Clues:

• Swear going in and out of All Soul's College
• Sons leave Los Angeles to make a point concerning defamation
• Contend
• Declare or accuse without proof
• Declare to be true
• A school loses business claim
• Maintain alcoholic drink is about litre, say
• Aver
• Claim the whole of it? Gee!
• 'Claim everything - the East, for instance (6)'