34 C.F.R.  §300.515.  Surrogate parents.

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(c) Criteria for selection of surrogates.

(1) The public agency may select a surrogate parent in any way permitted under State law.
(2) Except as provided in paragraph (c)(3) of this section, public agencies shall ensure that a person selected as a surrogate--

(i) Is not an employee of the SEA, the LEA, or any other agency that is involved in the education or care of the child;
(ii) Has no interest that conflicts with the interest of the child he or she represents; and
(iii) Has knowledge and skills that ensure adequate representation of the child.

(3) A public agency may select as a surrogate a person who is an employee of a nonpublic agency that only provides non-educational care for the child and who meets the standards in paragraphs (c)(2)(ii) and (iii) of this section.