I can't speak directly on either case since I wasn't involved with them but I can give some generalities.
In the George Waters case it involved much more than just Iowa. It was a multi-state/federal investigation. Yes, it took many years, but in the beginning though the DNR had information on him, my understanding is that there wasn't enough to do anything with it. I've had cases where we get information from the public that they believe is good and credible, but is insufficient to either get a search warrant or to issue a citation. So that information is filed away as another piece of the puzzle until something more comes along. In cases of this magnitude the investigation leads to more people who have to be interviewed, information processed, and with this case having federal involvement, you are looking at other states conducting their interviews/investigations and having to wait for them to get back with you. Yes, sometimes some earlier violations may not be prosecuted because of time involvement (more a state problem than federal), and a few more animals illegally killed before charges are finally brought. That is decision that is made by the people involved.
Again with the Decatur case, sometimes an investigation reveals illegal activity from previous years. Unfortunately, all Iowa fish and game violations are simple misdemeanors, and after one year of taking place, we (DNR officers) can't charge them with any violation. An example is if you illegally shot a deer on Sept 1, 2003 and we found proof about it on September 2, 2004 we coulnd't do a thing about it.
I can't stress enough having the public contact us when they think they see some illegal activity. Even if you're not sure, contact your local conservation officer and let them make the determination if the activity was illegal or not. So often CO's receive a call, days, weeks or even months later about some possible illegal activity. Most of the time by then it is too late to do anthing. Contact us immediately.
As I said in the beginning these are just some generalizations on these two cases. Sometimes there seems to be the public perception that as soon as CO's (or any other law enforcement officer/agency) gets some tip that they can rush out and issue a citation. It's not like TV where we can wrap up the case in one hour (minus the commercials).
Hopefully this answers your question.
Doug Clayton
State Conservation Officer