posting of journal entries

resposibility1 has access to one BS1 resposibility2 has access to one BS1 & BS2 The user with resposibility1 is able to post jounrnals both for BS1 & BS2 but we want the user with resposibility1 should only be able to post jounrnals with BS1 how this can be achieved.

Security rule does not 've

Security rule has no control on GL posting. Its used for reporting, journal creation, mass allocation, FSG etc