Balanced-budget rules not linked to expenditurelimits, such as America's Gramm-Rudman-Hollings act of 1985 and the European Union's Stability and Growth Pact, have been less successful.
That ruling, which also banned any limits on candidates' expenditure on free-speech grounds, has bedevilled attempts to curb the huge amounts of cash pouring into American politics, and it remains an obstacle to most current proposals for campaign-finance reform.