Federal Bureaucracy refers to those unelected and administrative body in the the Executive Branch of government.
Examples of the Federal bureaucracies include:
Social Security Administration
Internal Revenue Service
Veterans Benefits Administration etc
The federal bureaucracy does function well as discretionary authority under the democratic element of government because it is appropriately checked.
In conclusion, it is true that federal bureaucracy operates with sufficient checks and balances because each administrative body are monitored by independent auditors who aims to check its operational practice.