Conduct charges brought against 20 of the world's largest banks — including fines, legal bills and compensation for mistreated customers — totaled £264 billion during the five years up to the end of 2016, representing a 32% increase on the 2008-2012 period, according to a new report from CCP Research Foundation.

Ten years after the start of the global financial crisis, questions remain about whether banks really have improved their behavior and culture, according to the report's co-author Roger McCormick, a managing director at CCP, which provides research on bank conduct and ethics.

"We must hope that it has and that the efforts banks say they have been making to make changes for the better are bearing fruit, and that there is more to 'restoring trust' than a mere PR exercise," he wrote.

Bank of America Corp. ran up the highest level of conduct charges, at £45.59 billion during the 2012-2016 period, compared to £54.70 billion between 2008 and 2012. The most recent total included a £1 billion provision for anticipated future charges. Among European banks, Royal Bank of Scotland Group Plc had the largest level of conduct charges, at £21.51 billion, including £11.03 billion in provisions. The total for the period was a vast increase over the 2008-2012 figure of £4.56 billion.

Missold mortgages

Mortgage-related misselling was the single largest cause of conduct charges during the five year period, accounting for £65.84 billion in charges. This was followed by fines categorized as being for other failures in governance or management, at £32.47 billion, and £26.89 billion for fines relating to personal protection insurance, or PPI, misselling. Other reasons for conduct charges included defective internal controls (for example, in the case of a rogue trader); contravention of sanctions; market-related abuses such as insider trading; and breaches of client confidentiality.

Fines for PPI will come to a natural end "eventually," although U.K. banks will have to make additional provisions of over £1.5 billion halfway through 2017, McCormick noted.

Ten years on from the start of the global financial crisis, the level of conduct charges still being paid by banks is "striking," wrote Chris Stears, research director at CCP Research Foundation. Looking forward, the large sums of money still being set aside for anticipated conduct charges is concerning, he added.

"While we might have expected conduct costs to have increased over the period — 2016 was, after all, a significant year as cross-jurisdictional regulatory enforcement actions and various private suits settled and costs crystallized — we would not have expected the level of provisions to remain largely unchanged," he wrote. "If we are to look for an indicator of the effectiveness of the industry's efforts in changing its culture, promoting good behavior through appropriate incentives and standards and in managing conduct risk, this report's findings make for illuminating reading. Trust in, and the trustworthiness of, the banks must surely correlate to (and be conditional on) banks' conduct costs."

Provisioning at the end of the 2012-2016 period totaled £63.37 billion, up from £60.71 billion at the end of 2015 and £59.04 billion at the end of 2014.