28 CFR § 45.2 - Disqualification arising from personal or political relationship.
(a) Unless authorized under paragraph (b) of this section, no employee shall participate in a criminal investigation or prosecution if he has a personal or political relationship with:
(1) Any person or organization substantially involved in the conduct that is the subject of the investigation or prosecution; or
(2) Any person or organization which he knows has a specific and substantial interest that would be directly affected by the outcome of the investigation or prosecution.
(b) An employee assigned to or otherwise participating in a criminal investigation or prosecution who believes that his participation may be prohibited by paragraph (a) of this section shall report the matter and all attendant facts and circumstances to his supervisor at the level of section chief or the equivalent or higher. If the supervisor determines that a personal or political relationship exists between the employee and a person or organization described in paragraph (a) of this section, he shall relieve the employee from participation unless he determines further, in writing, after full consideration of all the facts and circumstances, that:
(1) The relationship will not have the effect of rendering the employee's service less than fully impartial and professional; and
(2) The employee's participation would not create an appearance of a conflict of interest likely to affect the public perception of the integrity of the investigation or prosecution.
(c) For the purposes of this section:
(1) Political relationship means a close identification with an elected official, a candidate (whether or not successful) for elective, public office, a political party, or a campaign organization, arising from service as a principal adviser thereto or a principal official thereof; and
(2) Personal relationship means a close and substantial connection of the type normally viewed as likely to induce partiality. An employee is presumed to have a personal relationship with his father, mother, brother, sister, child and spouse. Whether relationships (including friendships) of an employee to other persons or organizations are “personal” must be judged on an individual basis with due regard given to the subjective opinion of the employee.
(d) This section pertains to agency management and is not intended to create rights enforceable by private individuals or organizations.