Paragraph 15
A determination of the Secretary of State (including a determination made following a change of circumstances) whether a person is, or is to be treated as, capable or incapable of work shall be conclusive for the purposes of any decision which falls to be made—
(a)
under a relevant enactment; or
(b)
on a claim for or award of—
(i)
housing benefit; or
(ii)
council tax benefit.