Ukip firebrand Nigel Farage and Liberal Democrat leader Nick Clegg were both wrong when they clashed over how much UK law comes from Brussels, according to a major study.
Business for Britain (BfB) found that 64.7% of the laws in force in the UK today either originate from the European Union (EU) or are deemed to be EU influenced by the House of Commons Library.
The analysis, which combined House of Commons research and the campaign group's own examination of EU regulations, also revealed that EU regulations accounted for 59.3% of all UK law between 1993 and 2014.
The figures are contrary to Farage's claim, who quoted former European Commissioner for Justice Viviane Reding, that 75% of UK law originates from Brussels.
Likewise, the data also leaves Clegg red faced after he claimed in the TV debates in the run-up to the EU elections that only 7% of British laws came from the continent.
BfB called for a "significant reduction" in the amount and scope of EU legislation and powers over certain policy areas.
"Access to the Single Market should not come at the cost of having two thirds of our laws being decided by the EU," said Matthew Elliott, chief executive of BfB.
"There must be a significant reduction in the amount and scope of EU legislation and powers over certain policy areas should be given back to Parliament so decisions are made far closer to the British people."
The data comes with 65 days to go before the general election in May, with the Tories and Labour neck-and-neck (34% vs 34%) in the latest poll from YouGov.
Cameron has promised that a Conservative government would give the electorate on the UK's membership on the EU in 2017.
But Ed Miliband has maintained that he wants the UK to stay within the economic and political union.
Eurosceptic party Ukip have made some big political gains in recent years and have called for the UK to exit the EU.
The organisation, led by Nigel Farage, won the EU elections in the UK last year but they have since dropped in the opinion polls to around 15%.