By how steve s family supported him. it s a large family. very educated, very tight-knit group. how uniformly did they support steve through this process? i d say very uniformly. they re all behind him? yes. reporter: but one thing after another. as steve s second trial approached there was another, huge, surprise. the source of the dna found under carol s fingernails was finally identified. that would be mr 603. coming up we had exhausted so many man hours and looked at any and all alternatives. we finally were able to discover and verify who mr. 603 is. the mysterious pl 603, not who anyone expected.