With foreclosure sales steadily rising, four states are concerned that the use of the foreclosure sale prices in appraisals of neighboring homes is distorting the market. Legislators in Illinois, Nevada, and Missouri have all proposed separate bills that would exclude or restrict foreclosure sales from being used as comparisons to determine the value of homes around them. Maryland had proposed a similar bill, but withdrew the legislation on 3/31/11.
http://www.dsnews.com/articles/three-states-move-to-ban-foreclosure-sales-from-appraisal-values-2011-03-30