Here is what i'm looking for:
select author_uid, tagged_uids, page_id from location_post where author_uid = me() or ( author_uid in (select uid2 from friend where uid1=me()) and me() in tagged_uids)
When i split the queries they return the expected results.
i.e, both
work as expected. What I need is a union of the 2. I'm tempted to say this is either a bug (or a limitation) in the API
Note:
The problem was me() in the query. I had the user's ID around and replace me() with the actual ID did the the job
SELECT id, author_uid, page_id, tagged_uids, timestamp, coords FROM location_post WHERE (<id> IN tagged_uids or author_uid = <id>)