What is the French expression for "closing the barn doors after the horses have fled"?

France's finance minister, Christine Lagarde, is calling for tighter bank controls after a single trader caused Société Générale to lose more than $7 billion.

"Very clearly, certain mechanisms of internal controls of Société Générale did not function, and those that functioned were not always followed by appropriate modifications," Lagarde said to reporters after submitting her report, according to the BBC.

It is the first government report on the trading scandal. The Bank of France is also investigating, while the independent directors of Société Générale are conducting their own inquiry. Meanwhile, Paris prosecutors are continuing a criminal investigation.

And those aren't all. Kara Scannell of the Wall Street Journal reports that the United States Securities and Exchange Commission is investigating some $140 million in sales of Société Générale shares by Robert Day, investment manager of the Trust Company of the West, and two foundations associated with him. The stock was sold in the second week of January, before the trading scandal broke.

The United States attorney has also begun an investigation related to Société Générale, the Journal says, "although its precise focus wasn't immediately clear."

A spokesman for Day told the Journal that the trades were permitted under the bank's policies and that all disclosures were made. "No inside information was used in any way with respect to these sales," the spokesman said.

In the finance minister's report, Reuters points to what appears to be "the most damning conclusion": Last year, inspectors from the Bank of France found Société Générale's securities procedures lacking.

Lagarde also called for greater penalties for fraud.

Still, she said that it was not certain that the unwinding of positions by Société Générale was responsible for the sharp slide in European markets on January 21.