The Ninth Circuit determined that section 273a(a) of the California Penal Code is an indivisible statute; that is, a jury need not decide if a defendant engaged in intentional conduct (injurying a child) or negligent conduct (permitting a child's safety to be placed in danger). Because negligent conduct is insufficient to qualify as a crime of violence, a conviction under this subsection is not a crime of violence aggravated felony.
The full text of Ramirez v. Lynch can be found here: http://cdn.ca9.uscourts.gov/datastore/opinions/2016/01/20/08-72896.pdf