Are policy and legal references available for the DoD CIO authorities and mission?
What is the recommended division of labor between the CIO and the Acquisition Executive?
Please see DoDD 5144.02, "DoD Chief Information Officer (CIO))," November 21, 2014.
US Statutes, DoD Policies are listed here. Roles, Responsibilities and mission is listed here.
The responsibilities of the PEO CIO would be found in paragraph 4. Substitute PEO/Acquisition Executive for the Secretary of Defense.
You can also look at one of the Service's CIO models:
Click on "About CIO"
Click on "IT Policy & Guidance"
Air Force: http://www.safcioa6.af.mil/
Click on "SAF/CIO A6 Mission Brief"
Example, PEO CIOs:
Army PEO EIS: http://www.eis.army.mil/
CIO: Mr. Patel
Click on "ABOUT"
Click on "CONTACT" and request a copy of the CIO Charter