Tax Collectors are a special type of enemy. They are backed up with a small squad of soldiers and are usually in the process of shaking down people for money. This is a good way to practice your chain kills or to quickly dispatch a larger group.
Alternatively they are a single individual running around the city. Connor can track them down and tackle them. Doing this will give you a nice bit of money for your trouble.
Be wary of either as defeating or tackling them will raise your notoriety.
