It's unfortunate that the penalties are not stiff enough to deter people. Same goes with another situation that I had to go through recently, someone abused one of my dogs several weeks ago while NoobDeBiff and I were at work. Ended up cutting a chunk of her leg off, 5 inches by 5 inches in size. She had to be taken to the emergency vet and had over $1000 and six hours worth of emergency surgery.
The vet was dumbfounded as to how this could have happened, and suspected it was a person, as her leg was not bitten or torn, or anything like that, it appeared to have been cut. And NoobDeBiff did not find the chunk of flesh, any fur or any blood anywhere in our yard. To top it off, around the same time, I received an anonymous letter threatening my dogs (neither of them are aggressive and neither of them bark. One of my neighbors commented that she didn't even know I had dogs when I asked her if she had seen anything suspicious going on that day).
I consulted a lawyer, and she advised me to file a police report and call animal control, but they wouldn't even do that for me, this was not an issue that was worth addressing to them. It's just too easy for people to get away with stuff like this (and the illegal harvesting of wild animals) when there seems to be no punishment (or in my dog's case, even investigation) for the perpetrators.