Well, Thanet did manage to redeem himself by the end, though it took way, way too long.
The resolution to the mystery involved a bit of a deus ex machina type situation in that
Thanet suddenly remembered he's seen a known petty criminal in the crowd at the murder scene, and that he suspects the criminal witnessed the murder, and lo and behold he did. Of course, by this point, Thanet had a sudden revelation the night before while in bed in which he figured out the murderer, but needed proof. He then remembers the petty criminal.
These aren't horrible books, and they're well written, I just don't think they're for me. Moving on now.