Europe’s banks are eager to show that the money they’ve splurged on bolstering their compliance departments is paying off: HSBC Holdings Plc’s reporting of a suspicious transaction helped Angola recover $500 million linked to an alleged fraud involving the son of a former president.

The bigger picture is less encouraging. Despite a cascade of rules, regulations and record-breaking fines, that spending — an additional 5 billion pounds ($7 billion) a year in the U.K. alone — has barely moved the needle. Gauging success in this area may not be an exact science, but if catching dirty money is a viable metric, it looks like little progress has been made.

Pan-European crime-busters Europol reckon only about 5 percent of transactions firms identify as suspicious is reported to the authorities, of which 10 percent leads to further investigation. That’s a conversion rate of less than 1 percent, suggesting banks are prophylactically over-reporting data rather than providing valuable information that that can lead to arrests.

Part of the problem is the spaghetti of rules and varying approaches to enforcement taken by top financial centers. Duplicated guidance, confusion over what is a requirement rather than best practice, and conflicting advice from consultants are all common bugbears for bankers.

The authorities are trying to tackle this. The U.K., home to Europe’s biggest financial center, is promising to improve transaction reporting as part of a drive to properly tackle the 90 billion pounds of money the National Crime Agency reckons is laundered every year in the country.

There remains a lack of consistency across sectors. Banks are a crucial conduit for dirty money — but criminals also benefit from lawyers, estate agents and casinos, which aren’t always subject to the same oversight. Bigger fines might be a welcome deterrent here. One U.K. law firm found to be in breach of money-laundering regulations was fined the grand sum of 50,000 pounds — less than a year’s earnings for a junior city lawyer.

The bigger problem is political. The U.K. says all the right things about corruption and corporate crime, but it can also be relaxed about investigating and prosecuting it, something my Bloomberg Businessweek colleagues reported on in February. Look how the conviction rate for financial crime has fallen and how close the government came to shutting down the Serious Fraud Office.

This isn’t just a British problem. Recent bank scandals in Latvia and Malta show how dependent the money-laundering fight is on national authorities, and how variable their track record can be.

All this should give investors pause for thought when they consider whether more spending on technology will help banks solve their compliance woes. Artificial intelligence will certainly help analyze their haystacks of data, but it won’t fix the political obstacles to sharing it.

Since U.S. regulators walloped HSBC with a record fine for compliance failings in 2012, others in the industry have been anxious to avoid getting hit in the same way. On that measure, the spending has broadly paid off. The bulk of European banks’ fines for misconduct are probably behind them and, in December, the U.S. lifted its threat of a criminal prosecution of HSBC.

But the idea of virtue being its own reward looks bizarre given the evidence showing financial crime isn’t shrinking. There now needs to be a greater focus at the political level on how to share data between institutions and national authorities. With Brexit threatening regulatory divergence, and renewed concerns over data privacy in the public, that won’t be easy. But it might prove more useful than another round of spending on compliance.