Section 25: Membership of a terrorist group or proscribed entity.

(1) A person who is a member or professes to be a member of a terrorist group or a proscribed entity, in or outside Nigeria, commits an offence, and is liable on conviction to imprisonment for a term of at least 20 years and up to a maximum of life imprisonment.
(2) It shall be a defence for a person charged with an offence under subsection (1) that—
(a) the entity, in respect of which the charge is brought, was not a terrorist group or a proscribed entity at the time that person became a member or began to profess membership of that group or entity; and
(b) the person has not taken part in the activities of that group or entity, after it became a terrorist group or proscribed entity.
(3) A person who belongs or professes to belong to a proscribed entity, in or outside Nigeria, commits an offence, and is liable on conviction to life imprisonment.
(4) It shall be a defence for a person charged with an offence under subsection (3) that—
(a) the entity, in respect of which the charge is brought, had not been designated to be a proscribed entity at the time the person charged became or began to profess membership of the entity; and
(b) the person has not taken part in the activities of that entity at any time after it has been designated to be a proscribed entity.