TL;DR Top-down control and decent pay. Long Version Compartmentalizing access and control to important processes makes it hard for anyone at a lower level to

TL;DR Top-down control and decent pay. Long Version Compartmentalizing access and control to important processes makes it hard for anyone at a lower level to take a bribe. For instance, you couldn't pay off somebody at your local DMV for a license or ID, since the clerk has to enter your provided values (SSN, forms of identification) into a system that is out of their control. It's not impossible, just difficult. Paying employees enough (government employees are typically overpaid when comparing their salary / job duties to similar private sector positions) to keep the difficulty/risk:reward ratio moderately high reduces, using basic economics, the risk of corruption. On the Contrary Keeping controls at a high level, and removing discretion puts the power in the hands of the few. And, as we've all heard before, power corrupts. Worth noting, however, is that power doesn't so much corrupt as does the intrinsic problem solving skills of the human mind. The idea that power corrupts is a false attribution fallacy applied to something that is grossly noticeable (nobody notices when somebody speeds a little or steals a pen from work, but when it's something large (affected by somebody in power), it becomes noticeable). The point is that the lack of corruption at a lower level indicates a mathematical inevitability of corruption at a higher level (e.g., the cozy relationships between Fannie May and Freddy Mac and various Senators, namely our current president)).