i'm craig heeps for a second look. >> when we come back on a second look, the investigations into whatned at waco. a bit later, disturbing testimony from a 14-year-old girl about branch devidian leader david koresh. >>> tonight a second look revisits the siege of the branch devidian compound in waco texas 20 years tonight. it was easy to see what went wrong in waco. the question is why it went wrong. government cover ups had muddies the water more. craig heaps had this look at this investigation that followed the siege in waco. >> reporter: in the days after the siege ended in the smoking ashes of waco lay many questions and few answers. formost among the questions what went wrong with the original raid and how did that deadly fire start that ended the siege. when they first approached the compound, atf agents were relying on the element of the surprise. but the branch devidian seemed to know they were coming. >> we had everything, the intelligence, what we had was someone who eliminated the element of surprise which is what we needed and in so doing our agents walked into an ambush an