28 CFR §24.106

1. (a)A prevailing applicant may receive an award for fees and expenses incurred in connection with a proceeding unless (1) the position of the Department as a party to the proceeding was substantially justified or (2) special circumstances make the award sought unjust. No presumption arises that the agency's position was not substantially justified simply because the agency did not prevail.
2. (b)An award will be reduced or denied if the applicant has unduly or unreasonably protracted the proceedings.