 In 2001, the SPLC included these groups, and Tanton, in a list of inter-connected network of anti-immigration groups which espouse bigotry, either openly, or thinly disguised.In February 2009, the SPLC again described his views as racist.Tanton's environmentalist and anti-immigration activities are well-documented in 15 file boxes of archives he donated to the Bentley Historical Library at the University of Michigan.