SAN FRANCISCO -Standard & Poor's stood up for its municipal bond rating system in an article it released on Friday.

The credit agencies have come under fire for their rating policies, most recently from a letter last week signed by more than a dozen officials from major municipal bond issuers, saying "differential ratings standards" between tax-exempt debt and corporate debt have punished municipal issuers with unfairly low ratings.

Subscribe Now

Independent and authoritative analysis and perspective for the bond buying industry.

14-Day Free Trial

No credit card required. Complete access to articles, breaking news and industry data.