The lag's record, or who may have access to it (9)
I believe the answer is:
constable
'who may have access to it' is the definition.
I can't tell whether this defines the answer.
'the lag's record' is the wordplay.
'the lag's' becomes 'cons' (both can mean a convict).
'record' becomes 'table' (I've seen this before).
'cons'+'table'='CONSTABLE'
'or' is the link.
Can you help me to learn more?
(Other definitions for constable that I've seen before include "See 1" , "In England, a great painter or lowly policeman" , "Bobby" , "Force member" , "CARRY ON FILM" .)