Want to create View or Function to contain security code and access in WHERE clause

create or replace function "GET_ACCESS"
(pPID NUMBER, 
 pUSER_TYPE in VARCHAR2,
 pPAGE_TYPE in VARCHAR2)
return BOOLEAN
is
    lcnt NUMBER;
begin
  CASE
     WHEN pPAGE_TYPE='ENTER' THEN
         select count(*) into lcnt
	from AUDIT_USE U, AUDIT_TEMPLATE T
	where U.AUDIT_TEMPLATE_ID = t.AUDIT_TEMPLATE_ID
	  AND ( (pUSER_TYPE IN ('ADMIN','TPM')) 
	     OR (pUSER_TYPE IN ('CLIENT','SUPER') 
		   AND U.AUDIT_TEMPLATE_ID IN
		    (Select AUDIT_TEMPLATE_ID from SECURE_TEMPLATE
			where PID = pPID 
		  	  and (ALLX = 'Y' OR AUDIT_AUTH = 'Y')
		     )
		 )
	       );
     WHEN pPAGE_TYPE='EDIT' THEN
       select count(*) into lcnt
	from AUDIT_USE U, AUDIT_TEMPLATE T
	where U.AUDIT_TEMPLATE_ID = t.AUDIT_TEMPLATE_ID
	      AND ( (pUSER_TYPE = 'ADMIN') 
	         OR (pUSER_TYPE = 'TPM' AND U.AUDITOR_ID IN 
                     (select PID from PERSON where user_type = 'TPM')
                     )
		 OR (pUSER_TYPE IN ('CLIENT','SUPER') 
 		    AND t.AUDIT_TEMPLATE_ID IN
		        (Select AUDIT_TEMPLATE_ID from SECURE_TEMPLATE
		             where PID = pPID 
		             AND (ALLX = 'Y' OR AUDIT_AUTH = 'Y')
		         )
		     )
		   ); 
     WHEN pPAGE_TYPE='VIEW' OR pPAGE_TYPE='REPORT' THEN
       select count(*) into lcnt
	from AUDIT_USE U, AUDIT_TEMPLATE T
	where U.AUDIT_TEMPLATE_ID = t.AUDIT_TEMPLATE_ID
	  AND ( (pUSER_TYPE IN ('ADMIN','TPM'))
	     OR (pUSER_TYPE IN ('CLIENT','SUPER') 
		AND t.AUDIT_TEMPLATE_ID IN
		   (Select AUDIT_TEMPLATE_ID from SECURE_TEMPLATE
			where PID = pPID 
			AND (ALLX = 'Y' OR AUDIT_AUTH = 'Y')
		   )
		 )
	     OR (U.EXAMINER_ID = pPID AND U.COMPLETE = 'Y')
	     OR (pUSER_TYPE = 'SUPER' 
		  AND (U.EXAMINER_ID = U.SUPERVISOR_ID   
		  OR   U.EXAMINER_ID IN (select E.PID
			           from PERSON E, PERSON S
			          where S.PID = pPID 
		           and E.REPORTS_TO_1 = S.position_id 
		            OR E.REPORTS_TO_2 = S.position_id 
		            OR E.REPORTS_TO_3 = S.position_id 
		            OR E.REPORTS_TO_4 = S.position_id 
		         ) 
		       )
	         )
	       );
  END CASE;
  
  if(lcnt >0)then return true; end if;
  return false;
end;