It's a shame to see that fish dead. You would think that in 2015 where everyone has a cell phone with a good enough camera, a bunch of pictures would be enough. I show people my fishing pictures all the time on my phone or upload them onto social media like facebook.
With a catch that size, I would probably take a few more of the fish with a tape measure or even a short video (which everyone phone has).
It's within their legal rights to do whatever they want, just sad to see.