When a person receives a notice from NAB to appear in an inquiry, it can be for two purposes:-
1. An inquiry is opened against alleged corruption of such person by the institution of National Accountability Bureau, or
2. A person's statement is required in the inquiry opened against a third person with whom such person has ever transacted
In both scenarios the persons summoned by NAB are required to appear before the concerned Investigation officer. NAB generally opens up an inquiry on the applications received by credible sources to investigate a matter.
A lawyer cannot plead the case of his client at the departmental inquiry stage. However he can be consulted for best course of action to be adopted at such stage.
For more, you can consult firstname.lastname@example.org or call +923123450006