Of course he is. Any street fighter knows that the best locations to deliver a punch are the back of the head (a "rabbit punch"), or the temple. These sites are more likely to produce a concussion, temporarily or permanently incapacitating one's opponent. The goal of any accomplished fighter is to produce an immediate brain injury.
But Officer Ian Walsh? He can barely beat up a teenaged girl:
Fortunately for Officer Walsh, the Seattle Police Department will not fire him for his incompetent pugilism. Instead, he's been sent for retraining.
Maybe next time he punches a jaywalker, he'll land a better blow.
Update: According to Packratt from Injustice Everywhere (a blog that everyone should read), this is only one incident in a long string of Seattle officers using force to eliminate the scourge of jaywalking.