mr. feit, i'm gary tuchman with cnn. i want to talk to you about irene garza. >> good for you. >> it's not surprising he doesn't want to talk about irene, because not only do irene's relatives and dale tacheny believe he killed her, so does every police officer and law enforcement agency that's dealt with this case. do you believe you know who the murderer is? >> we have developed evidence sufficient to the threshold responsibility of probable cause that john feit was a person involved in the particular homicide. >> but with so much heat, why did the case go cold? early on, why do you think he wasn't prosecuted? >> a cover-up. >> who are they trying to protect? >> john b. feit. has got it goin' on ♪ [ male announcer ] the beautifully practical and practically beautiful cadillac srx. lease this 2014 cadillac srx for around $319 a month with premium care maintenance included. ♪ >>> mcallen, texas, in the 1930s was segregated. the neighborhoods, the schools. even in the hospital, mexican-americans and anglos were treated in