Complex sentence: In January 2015, Brandon Darby, writing for Breitbart.com, published leaked internal training documents of the U.S. Customs and Border Protection that he described as "catch-and-release 2.0".
Split into simpler sentences: In January 2015, Brandon Darby, writing for Breitbart.com, published what he claims are leaked internal training documents of the U.S. Customs and Border Protection. He described them as "catch-and-release 2.0".