6. Any answers given or information furnished by a person in response to a requirement imposed under paragraph 2 or 3 may not be used in evidence against him except—
(a)on a prosecution for an offence under the [1979 NI 19.] Perjury (Northern Ireland) Order 1979; or
(b)on a prosecution for some other offence where evidence inconsistent with any such answers or information is relied on by the defence; or
(c)on a prosecution for an offence under paragraph 5.