(Bloomberg) -- Shadow Chancellor John McDonnell joined protesters outside the Bank of England marking a decade since the collapse of Lehman Brothers, urging that finance companies should provide for society.

“The key lesson is this,” said the opposition Labour MP, “never let the finance sector become the masters of the economy, when they should be the servants of the economy.”

McDonnell reiterated Labour’s call for a financial transaction tax on derivatives that would raise as much as 5 billion pounds ($6.5 billion) to pay for schooling and free childcare. The MP added that the party would tackle tax evasion and money-laundering to invest in the NHS, jobs and homes. “All that will come as we democratize our economy.”

Speakers at the event that drew about 100 people included activists from groups such as Disabled People Against Cuts, Robin Hood Tax Campaign and even an ex-trader from Citigroup Inc. They echoed former U.K. prime minister Gordon Brown’s view that the world is “sleepwalking” into another crisis.

The fundamental flaws of the financial system remain unchanged, Molly Scott-Cato, a U.K. member of the European Parliament from the Green Party, told Bloomberg.

“We still have banks that pose a systemic risk. We should’ve addressed that and we haven’t,” Scott-Cato said.

To contact the reporter on this story: Laura Hurst in London at lhurst3@bloomberg.net

To contact the editors responsible for this story: Alaric Nightingale at anightingal1@bloomberg.net, Charles Daly, Steve Geimann

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