User blog comment:Master Sima Yi/Assassinews 05-08-'14 – Assassin's Creed: Rogue leaked video/@comment-3446336-20140805110247/@comment-2142534-20140805124514

Well, he has Templar marks all over, so he probably isn't a Templar who infiltrated into the Assassins.

1. He is killing an Assassin in the trailer.

2. He has Templar insignias on him.

3. He has a hood and hidden blade(s).

My guess is that he was an Assassin but turned Templar, and that Assassins know his true affiliation.