By Katy Burne and Aruna Viswanatha

A heightened emphasis by banking regulators and law-enforcement officials on financial misconduct may be constraining global growth, some officials warn.

Legal expenses are among the burdens weighing on banks, policy makers say. “The roughly $275 billion in legal costs for global banks since 2008 translates into more than $5 trillion of reduced lending capacity to the real economy,” Minouche Shafik, a deputy governor of the Bank of England, told a New York conference of regulators and bankers Thursday.

Other policy makers have expressed concern that strict crackdowns on banks’ lapses in carrying out anti-money-laundering regulations have led banks to nearly cut off several emerging markets from the global financial system, damping their economies. The International Monetary Fund, in particular, has sounded that alarm repeatedly this year and held a conference highlighting the issue at its annual meeting in early October.

Regulators say the fines and their enforcement actions reflect widespread misconduct in the industry, and that the way to reduce compliance costs is for banks to improve their behavior. Indeed, the event Ms. Shafik addressed—a Federal Reserve Bank of New York conference on “Reforming Culture and Behavior in the Financial Services Industry”—focused largely on new strategies that governments could adopt to further pressure banks to alter practices to better comply with existing laws.

Ms. Shafik blamed the high fines, and resulting costs to the economy, on “the wave of misconduct which has emerged in the aftermath of the financial crisis” and explained the BOE’s strategy for “better regulation” to “improve standards and ethics in financial markets.”

“There are certainly public costs” when banking culture falls short of regulatory expectations, William Dudley, president of the New York Fed, said at the conference. “To the extent we don’t have trustworthiness in banking…that actually undermines the effectiveness of the financial community.”

Even as many banks have cleaned up their books and restructured their businesses since the financial crisis, the cloud of compliance costs hangs over the industry’s outlook. Deutsche Bank AG ’s continuing negotiations with the Justice Department to settle unresolved allegations over crisis-era risky mortgages have hammered its stock price, as the company tries to talk the U.S. government down from its $14 billion settlement demand. Several other European banks, including Credit Suisse Group AG and Barclays PLC, are also expected to resolve similar claims in the coming months. The banks haven’t commented on any potential settlements other than to say they are cooperating with the investigations.

Banks have also paid multi-billion-dollar penalties in the past few years for alleged misconduct unrelated to the financial crisis, including processing transactions that violated U.S. trade embargoes, tax crimes and attempting to manipulate financial benchmarks. In 2015, five global banks agreed to pay $5.6 billion in combined penalties to end a criminal investigation into whether traders colluded to move foreign-currency rates for their own financial benefit.

It isn’t clear how much those penalties, or threats of penalties, have really crimped lending. Ms. Shafik attributed the $5 trillion figure in a footnote to her speech to “Bank of England staff calculations,” and didn’t elaborate on the methodology.

In the U.S. at least, banks in recent years have attributed tepid lending growth to lack of demand, not their inability to supply credit.

If anything, banks have been awash in deposits, which they have struggled to put to work. Over the eight years since the crisis took hold in the third quarter of 2008, loans as a percentage of deposits have averaged about 74%, according to Federal Deposit Insurance Corp. data. This means banks have had firepower to make additional loans.

Banks have changed their lending mix, especially when it comes to consumer loans and mortgages. In consumer lending, the biggest banks have focused mostly on only the most creditworthy borrowers. That makes them less susceptible to regulatory and legal issues.

“Postcrisis compliance costs on banks is one of the very reasons why capital is being allocated away from the banking industry and into the investment management space,” said Matthew Kerfoot, a finance lawyer at Dechert LLP in New York.

Meantime, banks say the anti-money-laundering rules have made it harder for them to do business outside advanced economies. “Banks’ risk appetite for providing…services to other banks is inevitably shrinking…banks are being more conservative in the services they offer banks, particularly in emerging markets and other high-risk jurisdictions,” Robert Werner, who heads financial- crime compliance for HSBC Holdings PLC, said at a Wall Street Journal financial regulation conference this week. “There’s going to be a tension then between the management of risk within an institution and the way that the functional regulators view that, versus policy makers who obviously want to have a robust international payment system,” he added.

“Large banks are withdrawing from smaller countries,” IMF Managing Director Christine Lagarde said in a July speech. While she didn’t call on regulators to ease up on enforcement, she did urge them to better communicate their expectations to banks.

This was the third year in a row that Mr. Dudley has convened a conference on banking culture. Officials made clear they don’t intend to ease up.

“We can mandate a good culture, but that’s not going to work,” Mr. Dudley told the group of around 250 central bankers, board members of banks, asset managers, academics and even a few organizational psychologists. “Regulation can’t keep up with the reality on the ground.”

Mr. Dudley repeated his call for a “bad banker” registry to track individuals accused of questionable values. This would require legislation to address existing employee- protection laws, he said.