I passed a deer sitting off the side of the road with it's head up and alert in broad daylight a few years ago. Ran my errand and it was still there when I came back an hour or so later, so I crept up on the shoulder of the road to check on it, poor thing tried to get up and run on at least a couple of broken legs, so I backed off and called the sheriff's deputy out. The guy came out, absolutely professional, checked the deer same as I had to make sure, filled out the paperwork and called in he was gonna shoot (real close to houses and other buildings, maybe 200 yards). Calmly walked close and as the deer tried to get up and move off, thrashing, he drew, aimed and fired in one smooth motion and drilled it straight through the head, instant kill. I was honestly impresssed by this cop's ability to shoot. I'd have a lot rather seen that deer get up and run off healthy, but at least it didn't suffer long.
Wife and kids came up on one a few years later after dark, called the sherriff and this guy didn't do so well, she said he seemed irritated and ended up having to shoot it several times. Wife was upset though she's no tree hugger.
I have gotten to where I'm real slow to kill anything anymore without a pretty good reason, I can kind of see me giving up hunting in the next few years other than just using it as an excuse to get in the woods. Along those lines, I have REALLY begun to get upset by seeing anything killed in a road. Such an unnatural state of events and no doubt caused damage to the driver's car and can also possibly cause injury to the driver. And for every one you see, no telling how many wandered off to die slowly.