Distinct In Common Table Expressions CTE

I have managed to write my first CTE SQL that handles recursion but I have a problem with distinct - can't get that to work!!

My CTE:
WITH StudentsHierarchy(SystemID1, GroupID, AccessType, AccessGroupID, StudentID, HierarchyLevel) AS
(
--Base Case
SELECT
SystemID,
GroupID,
AccessType,
AccessGroupID,
StudentID,
1 as HierarchyLevel
FROM UserGroup a

UNION ALL

--Recursive step
SELECT
u.SystemID,
u.GroupID,
u.AccessType,
u.AccessGroupID,
u.StudentID,
uh.HierarchyLevel + 1 as HierarchyLevel
FROM UserGroup u
INNER JOIN StudentsHierarchy uh ON
u.GroupID = uh.AccessGroupID

)
Select sh.SystemID1, sh.GroupID, sh.AccessType, sh.AccessGroupID, sh.StudentID, sh.HierarchyLevel, (select StudentName from Student s
where sh.StudentID = s.StudentID) AS StudentName from StudentsHierarchy sh
WHERE AccessType = 'S'

 

and I would like to have a distinct on the StudentID like:
Select DISTINCT sh.StudentID, sh.SystemID1, sh.GroupID, sh.AccessType, sh.AccessGroupID, sh.StudentID, sh.HierarchyLevel, (select StudentName from Student s
where sh.StudentID = s.StudentID) AS StudentName from StudentsHierarchy sh
WHERE AccessType = 'S'

 

 

How should I do?