The subpoena, made public Tuesday, commands the board to turn over records by Nov. 30 from two closed-session meetings.
Iowa's ombudsman sent a letter to the Iowa Public Information Board Nov. 2 demanding it turn over audio recordings and minutes of two closed-session meetings held over the summer.
The letter and subpoena were made public Tuesday in the IPIB agenda for its meeting Thursday in Des Moines.
One of the meetings under investigation took place Aug. 25 in which board members met in private for about an hour to discuss the fatal shooting of Autumn Steele by a Burlington police officer in Jan. 2015.
The Hawk Eye and Steele family are in the midst of a longstanding dispute to obtain investigative reports from the incident, including body camera, dash board videos and 911 calls from the Burlington Police Department and Iowa Division of Criminal Investigation.
IPIB chairwoman Mary Ungs-Sogard declined to provide any information following the closed-session meeting when asked to outline the parameters of what was discussed.
Following the secret meeting, the Des Moines Register filed a complaint alleging the board violated the state's open meetings law.
At the board's monthly meeting in September, it denied the ombudsman's request for access to records from the Aug. 25 meeting, citing attorney-client privilege.
The Office of the Ombudsman is an independent and impartial agency tasked with investigating complaints about state and local government, in addition to facilitating conversations between individuals and their government representatives.
In ombudsman Kristie Hirschman's Nov. 2 letter to IPIB, she wrote that in this case, the board "misapplied" attorney-client privilege.
"The Iowa Legislature has granted the Ombudsman authority to access closed-session records under chapter 21 without exception," Hirschman said.
The subpoena, also dated Nov. 2, "commanded" the board to produce audio recordings and minutes of the board's closed-session meetings on July 20 and Aug. 25 no later than Nov. 30.
Hirschman stressed in the letter that the closed-session records will remain confidential in her office's possession.
"It is inappropriate for you to raise the attorney-client privilege to deny my office access to records it clearly has a right to obtain under the law," Hirschman said.
Following the August meeting, Randy Evans, director of the Iowa Freedom of Information Council, called the board's actions indefensible and "a sadly laughable example of transparency."
Michael Giudicessi, who represented The Hawk Eye in its complaints against BPD and DCI before the public information board took over prosecuting the case, said the closed-door session was "breathtaking in its audacity."
The board's regularly scheduled monthly meeting will be Thursday in Des Moines.