Using CASE in the join statement in the AND clause. Where's the problem?

Question

All,
I have my code, where based on the case statement, I would like to restrict the number of records in my JOIN condition. It's the CASE statement that I have used, that's giving me the problem. Not sure, what the problem is. The error says (in my case expression):
Msg 102, Level 15, State 1, Line 59
Incorrect syntax near '>'.
Select a.Col1, a.Col2, b.Col1, b.Col2, b.Col3
From Table1 a
Join Table2 b
On a.id = b.id
Join Table3 c
On c.FiltId = a.FiltId
And
Case
When b.Col3 <> 5 --b.Col3 is an INT field
Then (b.OutDate >= DATEADD(DAY, -30, c.InsertDate) And b.OutDate <= DATEADD(DAY, 30, c.InsertDate))
When b.Col3 = 5
Then (b.InDate >= DATEADD(DAY, 5, c.InsertDate))
End
Join Table 4 -- Other Join conditions and where clause conditions

Answer 1

You do not know the CASE is an expression and fields are not columns. This is fundamental and probably means that a lot of your code needs work. 
You can probably re-write the query with something like this: 
SELECT A.col1, A.col2, B.col1, B.col2, B.col3
  FROM Table_1 AS A, Table_2 AS B, Table_3 AS C
 WHERE A.generic_id = B.generic_id
   AND C.foobar_id = A.foobar_id
   AND CASE
       WHEN B.col3 <> 5 
            AND (B.something_out_date 
                 <= DATEADD(DAY, -30, C.something_insertion_date) 
       THEN 'T'
       WHEN B.col3 = 5 
            AND (B.something_out_date 
                >= DATEADD(DAY, -30, C.something_insertion_date) 
       THEN 'T'
       ELSE 'F' END = 'T' ;
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