carlos and his brother benito were left with so many questions. >> we felt frustrated because we couldn't find out what happened, when my brother was killed and we didn't know anything. >> investigator deanfrom the mid-1990s. >> what did you want to take a second look at? >> at that time, dna in the mid- 90s was fairly new but it was also advancing rapidly. i simply requested that the crime lab re-examined the blood. >> the blood found in the transmission shop, the shop that the prime suspect, gianni van, had access to. the original dna test said the blood might be gonzalo's but it was far from certain. >> was there something different the second time around? >> there was significant change , although the crime lab couldn't say it was definitively mr. ramirez. the numbers were astronomical that it had to be his. >> more sophisticated testing lead to a stronger conclusion. >> mr. ramirez had been inside that transmission shop. >> so, in 2010, 15 years after the murder, investigator fulcher brought the case to prosecutor mike murri, who was known for his work on cold cases. intern, murray contacted gonzales brothers who says they were surprised to hear from him. >> both brothers said that