www.NFLConcussionLawsuits.com Principal Law Group » Blog » www.NFLConcussionLawsuits.com Posted on January 22, 2014 by Principal Law Group, LLP www.NFLConcussionLawsuits.comHomenflconcussionlawsuits.comWelcome to Principal Law Group, LLP in Washington, DC. A firm dedicated to helping current and former NFL Players suffering from long term effects of head injuries sustained while playing in the NFL.