California Gov. Jerry Brown, right, delivers his speech flanked by the head of the pontifical academy of Science, Bishop Marcelo Sanchez Sorondo, during a conference on Modern Slavery and Climate Change in the Casina Pio IV the Vatican, July 22, 2015.
California Gov. Jerry Brown, right, delivers his speech flanked by the head of the pontifical academy of Science, Bishop Marcelo Sanchez Sorondo, during a conference on Modern Slavery and Climate Change in the Casina Pio IV the Vatican, July 22, 2015. Alessandra Tarantino AP
California Gov. Jerry Brown, right, delivers his speech flanked by the head of the pontifical academy of Science, Bishop Marcelo Sanchez Sorondo, during a conference on Modern Slavery and Climate Change in the Casina Pio IV the Vatican, July 22, 2015. Alessandra Tarantino AP