The concept of due process is one of the most important in American law. Due process means having your grievance heard by a court or other legal body competent to decide your issue. For federal employees with employment disputes, it often means having a case heard by the Merit Systems Protection Board (MSPB).
The MSPB has been prevented from hearing cases involving positions that are considered national security "sensitive." An employee in one of these areas, facing an adverse job action that has no connection to issues of national security or classified information is denied the opportunity to bring their case to the MSPB.
Instead, they have to rely on the agency that is taking the adverse action to treat them impartially and fairly. This can be problematic when the issue involves elements of whistleblowing and retaliation.
One can hardly expect the agency that has been accused of retaliation of being capable of making an impartial decision when the decision makers involved may be the very parties accused of retaliation.
The MSPB offers employees the ability to make their arguments in front of an independent decision-making body that is unconnected to their agency. The MSPB exists to prevent employees from being left at the mercy of the very agency that they feel has wronged them.
A bill has been introduced in Congress that would restore the right to a hearing by the MSPB. The Senate sponsor said, "My bill prevents the government from denying federal employees their rights and makes sure the government can’t arbitrarily strip them of their jobs."
However, any legislation will have to address the issue of a Supreme Court case that prevents "non-expert" adjudication of matters pertaining to national security.
Source: vexe.com, "Lawmakers Want to Restore Due Process to Feds in 'Sensitive' National Security Positions," Eric Katz, December 16, 2013