Clue: Bamboozled Irish politicians (one caught napping?) (4,2,4,1,6)
Answer: DONE UP LIKE A KIPPER
Explanation: Definition: Bamboozled
A charade of DONEUP, an envelope ('caught') of 'one' in DUP (Democratic Unionist Party, Northern 'Irish politicians') plus LIKE A KIPPER ('napping'). Not an expression familiar to me, but it is in the Urban Dictionary.