sunshine law

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A law designed to provide the public with greater scrutiny of the governmental process, as through more public notice and disclosure of government actions and greater public access to decision-making meetings.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A law (rule enacted by a legislature or the like) that allows the general public greater knowledge of the actions of a government.