Well the intent goes beyond a university of cost of $0.5-M (the govt probably "misplaces" much more than that in a year), but its more about the claim that the fraudulent research could "cost" the country more than that if Mann's research was taken as gospel.
Found the main article here:
http://www.huffingtonpost.com/rep-ed-markey/just-in-time-for-hallowee_b_754228.html (I think I have to go wash myself as I feel soiled visiting that website) for the rantings of Rep. Ed Markey (D-MA).
For those of you that dont know, Markey is on the "Committee on Energy Independence and Global Warming." Researchers like Mann (as opposed to scientists who develop logical theories based on science) develop "supporting data" that gives more power to Markey's committee and justifies their existance. It is only logical that Markey would attemt to tar anyone who could be a threat to his committee's power and legitimacy. I love the soviet and witch-burning implications - very spooky. *eye roll*
Now, is it a waste of money to stomp on Mann's research? For the AG to do it, I do agree that it is a waste - its like using a cannon to kill a fly. You wont see much in the more "conservative" media, because they are more focussed on where we are going...and why are we in this handbasket.