# 9701.703 Definitions.
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.