The Fifth Circuit determined that "former informants," or people who report criminal activity the police, are not a cognizable social group for asylum and withholding of removal purposes. The Court found that the proposed group lacked social distinction and particularity.
The full text of Hernandez-De La Cruz v. Lynch can be found here: http://www.ca5.uscourts.gov/opinions/pub/14/14-60730-CV0.pdf