The First Circuit applied a de novo review to the BIA's determination that the IJ clearly erred when he determined that the Mexican government was unable or unwilling to protect the petitioner from organized crime members. The Court reversed the BIA's determination because it conflated the issue of the police's willingness to investigate the crime with their ability to actually protect the petitioner from harm. The IJ focused heavily on the country conditions evidence that police in Guerrero are overwhelmed by organized crime, and the First Circuit cited this analysis approvingly.
The full text of Justo v. Sessions can be found here: http://media.ca1.uscourts.gov/pdf.opinions/17-1457P-01A.pdf