Del. Code tit. 29, § 10129

No member or employee of an agency assigned to participate in any way in the rendering of a case decision shall discuss or communicate, directly or indirectly, respecting any issue of fact or law with any person or party, except upon notice to and opportunity for all parties to participate. This section shall not apply to communications required for the disposition of ex parte matters authorized by law or to communications by and among members of an agency, the agency’s staff and the agency’s attorney.