In this subpart:

Adjudicating official means an administrative law judge, administrative judge, or other employee designated by MSPB to decide an appeal.

Day means calendar day.

Harmful error means error by the Department in the application of its procedures that is likely to have caused it to reach a conclusion different from the one it would have reached in the absence or cure of the error. The burden is on the appellant to show that the error was harmful, i.e., that it caused substantial harm or prejudice to his or her rights.

Mandatory removal offense (MRO) means an offense that the Secretary determines in his or her sole, exclusive, and unreviewable discretion has a direct and substantial adverse impact on the Department's homeland security mission.

Mandatory Removal Panel (MRP) means the three-person panel composed of officials appointed by the Secretary for fixed terms to decide appeals of removals based on a mandatory removal offense.

MSPB means the Merit Systems Protection Board.

Petition for review means a request for review of an initial decision of an adjudicating official.

Preponderance of the evidence means the degree of relevant evidence that a reasonable person, considering the record as a whole, would accept as sufficient to find that a contested fact is more likely to be true than untrue.