it didn't add up. >> co-lead investigator tom fassbender worked with local sheriff's deputies but was a different agency -- the wisconsin department of justice. this is the first time he's responded publicly to the accusations against him and his law enforcement colleagues. >> did you have any kind of vendetta against steven avery? >> absolutely not. i didn't know steven avery, didn't know his family. never been there. >> fassbender bristles at the idea the local investigators could have done anything unethical. >> the people that were there that i worked with were hard-working. they only wanted to do the right thing and to do this investigation the right way. >> is it possible that that blood could have been planted? >> no. everything all the evidence says no. >> fassbender notes that a chemical calleedta had been used to preserve avery's blood in the vial. and that at trial, tests showed no presence of avery's blood found in the suv. >> it didn't match. >> fassbender's argument, since that blood found in the vehicle didn't contain the chemical, it couldn't have come from the vial. a