>> and forensic testing could not determine the origin of the blood in persitz's trunk. at the time, dna testing wasn't as sophisticated as it is today. >> back then, the dna testing procedures that we used required dna to be what's called high molecular weight. we needed dna that hadn't gone through any degradation processes at all. >> but investigators did find some suspicious damage to persitz's car. the car had damage to the front right end. the paint was scraped and the bumper was broken. the scratches on the bumper had what appeared to be tiny specs of orange paint, which were removed with a small probe. >> we're talking microscopic-sized chips of paint. >> the paint sample was compared to the paint from the broken gate using a process called a solubility analysis. >> chemical solubility tests are a series of reagents or