Not liable (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">not liable</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for exempt that I've seen before include "Permitted to be unaffected" , "Excused - let off" , "Freed from obligation, tax etc" , "Duty-free" , "Free from, eg, tax" .)
(Other definitions for immune that I've seen before include "Not liable to, protected from" , "Cannot be infected" , "Inoculated or exempt" , "Secure against, infection say" , "Resistant (to infection)" .)