All staff joining the Home Office require security clearance, and the level at which this is carried out is dependent on particular roles and responsibilities.
Staff are security cleared to Enhanced Baseline Standard level and some are additionally cleared at a higher level—Counter Terrorist Checks, Security Check or Developed Vetting. Where a higher level check is carried out an individual is asked to complete a questionnaire which asks about involvement in terrorism, sabotage or actions intended to overthrow or undermine Parliament by political, industrial or violent means. Where Developed Vetting is carried out—the highest level check—there is a mandatory face-to-face interview where these questions are put to individuals again and may be explored.
If at any stage of the vetting process, or subsequently, information comes to light that a person has any affiliations which give cause for concern, full inquiries are made and appropriate steps taken. These could include refusal or withdrawal of clearance or even dismissal. Against the background of these checks, it would be redundant to ask Home Office staff to declare membership of extremist organisations.