Originally Posted by John SWFC
I've just had this too. Completed the story, and I had a total of 227 clues found and no Magpie achievement. I then went back to replay the first story case because I only got 4 stars on it (because I really didn't know what I was doing at the time!) and the clue counter reset to 1. I finished the case finding all clues and the counter still only says 14 even though I've gone back to the free roam on the third disc to do a few street crime sidequests.
So I don't know if I've got to replay every case and find 95% of all clues again to get this achievement, or if it'll randomly unlock if I replay some cases and find a few clues that I missed in my first playthrough.
Well that's odd, the achievement actually unlocked whilst I was replaying the next case and interviewing a witness