With Sen. Arlen Specter’s shift to the Democrats, a question environmentalists may ask is “How well can we expect Sen. Specter to support environmental legislation, based on his past performance?”

The best guide we have to past performance are the League of Conservation Voters scorecards. Over the past ten years, Specter’s LCV score has ranged from a low of 14% in 2006 to a high of 60% in 2007, with an average score of 37%.  That erratic behavior is illustrated in Fig. A:

Recently Sen. Specter has been labeled as one of the few remaining Republican moderates, along with Senators Collins and Snowe of Maine. As far as support for the environment goes, that label might not be as accurate as we would like.  As seen in Fig. A, the Maine Senators have much higher LCV scores.

So how did Sen. Specter rank among the Republican Senators during the past ten years?  In Fig. B  we again see somewhat erratic behavior, with the top Republican LCV score in 2001 and as low as seventeenth in 2006:

This year Sen. Specter got off to a good start, voting for the stimulus bill and the omnibus public lands bill.  Let’s hope that he will move closer to the Maine Senators, even though he is now on the other side of the aisle.