Justice Jayne Jagot's Monday verdict against Standard & Poor's has triggered a global reassessment of ratings agencies' vulnerability to legal action over ill-considered debt ratings.S&P, Moodys and other agencies have been lambasted over the failure of many AAA-rated debt issues during the global financial crisis. But analysts have argued that US First Amendment rights and other legal hurdles protected the agencies from most civil liability. Monday's verdict in favour of 12 NSW councils which relied on S&P derivatives ratings has altered expectations of liability. It suggests that with enough evidence, and particularly in non-US jurisdictions, ratings agencies could yet be exposed to hefty legal claims.As of Tuesday night Australian time, the US stock market had slashed almost eight per cent from the value of S&P Parent McGraw-Hill over the course of two trading days. The capitalisation of Moody's Corporation fell almost six per cent in the same period.IMF, the litigation funder that backed NSW Councils, said yesterday that it had launched a second case against S&P and investment bank ABN Amro and plans other cases.Reuters commentator Felix Salmon said yesterday that Justice Jagot had found that S&P "used utterly bonkers assumptions in order to come to its conclusion ... Put it all together, and you get a very shocking view of S&P."The Financial Times website's Alphaville blog argued the decision "could well be a landmark case for credit ratings as causes of financial harm", and noted that the investors who relied on the ratings councils weren't given information in a way that would have allowed them to conclude the investments were high-risk.The Financial Times editorialised yesterday that "it is right that rating agencies should be held to account if they are negligent". But it added that "even if the ruling stands - and it will be appealed - it may not provide a durable solution to the problem of investor over-reliance on fallible ratings."