Wikipedia
Ag-gag is a term used to describe a class of anti- whistleblower laws that apply within the agriculture industry. Coined by Mark Bittman in an April 2011 New York Times column, the term "ag-gag" typically refers to state laws that forbid the act of undercover filming or photography of activity on farms without the consent of their owner—particularly targeting whistleblowers of animal rights abuses at these facilities. These laws originated in the United States, but have also begun to appear elsewhere, such as in Australia. Some of these laws, such as the failed proposal in Pennsylvania, have a wider scope and could be used to criminalize actions by activists in other industries.
Supporters of ag-gag laws have argued that they serve to protect the agriculture industry from the negative repercussions of exposés by whistleblowers. The proliferation of ag-gag laws have been criticized by various groups, arguing that the laws are intended primarily to censor animal rights abuses by the agriculture industry from the public, create a chilling effect in reporting these violations, and violate the right to freedom of speech.