This is the smallest falcon in North America.
I took this shot with her handler to give some perspective as to her actually size. People outside the US may be familiar with the Eurasian Kestrel, a larger but ‘look a like’ relative.
This is a young bird and I believe she was hit by a car. A very common injury unfortunately.
(Wikipedia) They are from 22 to 31 cm (8.7 to 12.2 in) in length with a wingspan of 51–61 cm (20–24 in).
Avian Conservancy, Charleston, South Carolina.