The anonymity in the civil service means that a civil servant

Explanation

The anonymity of the civil service is linked to two concepts: permanence and neutrality. Civil servants, many of whom remain in their jobs whilst serving numerous governments, are likely to have to give advice to governments of different political parties, who may have different attitudes to policy. 

 The advice they give needs to be given to ministers both freely and also without fear of adverse public or political reactions and without fear of future career damage.