Transcript for Mother visits Mexican authorities hoping for updates on missing son's case: Part 2
national forensics facility they tell us they have just 25 technicians working on identifying remains. Although the man in charge insists they care deeply about their work. So when you're doing your work, you're thinking of these families? Always. Always. They see the pain in the families, because they are the same persons to send us to collect samples from the families. They know -- they know their faces. Because we go to the sites, we hear his histories, we know his pain. Reporter: Of course there's another way, solve the crime and bring the perpetrators to justice. It's always hard. Reporter: But as Lucy Diaz knows, that is a struggle. We follow Lucy on her monthly trip around Mexico City to visit federal law enforcement authorities. I do get fed up for a minute. I say oh, my god. I get all this disappointment, and I feel down, depressed. You have to keep going. You can't stop. Reporter: Today she's headed to various investigative agencies to see if there are any updates on the case of her son Luis, now missing for six years. She leaves empty handed. Happens all the time. Reporter: Is it disappointing? I try not to think about it anymore, because that's exactly what they want. I get fid up. I get tired. I get frustrated and then just don't come back again. Reporter: So we decide to take Lucy's case directly to the president of Mexico, andrs Manuel lpez obrador, also known as amlo. He frequently campaigned with the families of the disappeared promising to help. Every morning he holds a press conference nationally televised and anybody can ask whatever they want to ask, so we're going to take advantage of that. We've been following closely the case of Lucy Diaz, one of the most prominent mothers in this country involved in the search for the disappeared. When we take a look at her case, it's clear there are many outstanding leads, and her allegation is that the police are refusing to follow up on these leads. I have a two-part question, first. If someone of her education and resources can't get justice in this country, can anybody? And two, would you commit here and now to using your new power taking a look at her case to see if you can move it forward? Thank you. He promises that one of his top officials will personally reach out to Lucy. Lucy catches the exchange on television. I hope that this wl lead to a little bit more investigation in my case. Reporter: I would think on one level, if the president of the country says all right, I'm going to pay attention to this case, you might think, all right, done. But I know how many times you've been disappointed. Yeah. Reporter: I'm curious, how do you set your expectations? If he doesn't do anything, I'll be massively disappointed this time. Because I never set my hopes so high. Reporter: It has now been nine months since the president of Mexico promised to intervene in Lucy's case. As of tonight, Lucy says she has not received so much as a phone call.
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