Intent is a very important thing to be considered in the legal system.No one should expect rewards for being honest nor pats on the back....honesty is a component found in people of good moral character. If the guy is sincerely honest and turned himself in, then he should be willing to accept the consequences for not knowing the difference between an antlered deer and one without.
Treating someone who accidentally shot an antlered deer and calls it in the same as someone who is deliberately shooting game out of season is akin to charging someone who accidentally ran over and killed a jaywalking pedestrian with 1st degree murder and seeking the death penalty. Or charging someone who shot and killed a drugged up thug in their home with 1st degree murder. Or spinning out on an icy road and running into a lamp post, then getting charged with felony destruction of property when you call in to report it. It is totally inappropriate and sends the message to the public that being honest is the worst thing you can do.
When being honest is punished just as much as being dishonest people will naturally be dishonest because being honest means reporting what you did while being dishonest means a decent chance that nobody will find out what you did. The zero-tolerance policies at school drilled this into me and my classmates and I find that very sad.
When people start to fear and distrust the Police/Game wardens and being dishonest is seen as safer than being honest, something is very wrong with the system. When "Shovel & Shut up" is seen by many as the "right" thing to do one needs to look at and see where these mindsets come from.
Sure one shouldn't expect a reward for being honest in such a situation, however they also shouldn't have to worry about getting totally screwed over by law enforcement when they call in to report their mistake.