Former Welsh politician avoids criticising fancy jewellery (5)
I believe the answer is:
bling
'fancy jewellery' is the definition.
(bling can mean jewellery)
'former welsh politician avoids criticising' is the wordplay.
'former welsh politician' becomes 'AM' (Assembly Member, old term for a Welsh politician).
'avoids' suggests deleting specific letters.
'criticising' becomes 'blaming' (blaming is a kind of criticising).
'blaming' with 'am' taken away is 'BLING'.
(Other definitions for bling that I've seen before include "Jewellery for show" , "Showy jewels etc" , "Flashy, ostentatious jewellery" , "Jazzy" , "Showy jewellery" .)