Hector Sants' break from his role as chief compliance officer at Barclays due to "exhaustion and stress" has highlighted the increasing strains on banks' internal policemen.
Compliance, the part of the bank which polices its activities for illegal or suspicious trades, has traditionally been one of the more sedate areas of the financial world, lacking the long hours, snap decisions and potentially huge rewards of the trading floors.
Yet in the past couple of years, many of those working in compliance are now working longer hours and facing more demands than colleagues in the front office, industry professionals say.
"The complexity of processes has really been ramped up," Sally Bernstein, co-leader of ethics and compliance services at PwC, told CNBC.
"Now everybody is highly regulated, there are a lot of demands."
(Read more: Barclays exec takes leave for stress)
And the importance of compliance can be seen both in the increased power granted to compliance officers – and the corresponding rise in their salaries. The number of U.S. compliance heads who report directly to their chief executive rose from 20 percent in 2012 to 28 percent this year, according to a recent study by consultants PricewaterhouseCoopers (PwC).
"While financial services firms have reduced headcount elsewhere, they are still hiring in compliance," Aaron Bolton, senior consultant at recruitment company Black Swan, told CNBC.
And the problem is not limited to financial services. The accusations of bribery directed at several pharmaceutical companies' Chinese operations, including Novartis, GSK and Eli Lilly, shows how other industries are affected by failure to enforce the same standards across their global operations.
(Read more: JP Morgan ramps up compliance spend)
Sants' move had raised eyebrows because he had been no stranger to stress earlier in his career. The appointment of such a heavy-hitter, with a seat on the board (which not many compliance officers have), was seen as a clear signal from Barclays that it was serious about cracking down on dangerous activity after being found to have played a major role in rigging a key overnight banking rate known as Libor. The scandal costs a raft of top executives at the bank – including chief executive Bob Diamond -- their jobs.