 Chambers (born c. 1956) is deputy head of the Sovereign Debt Ratings Group and chairman of the Sovereign Debt Committee at Standard and Poor's (S&P).Along with David T. Beers, Chambers earned significant attention in August 2011 for his role in downgrading the credit rating of United States Treasury bonds to AA+.Prior to this, the United States had maintained a AAA credit rating since 1941.