Dateline | December 06, 2013
>> it had been about a year since marie singleton's body was found in the trunk of her car at a los angeles beach. her son marcus, 8 years old at the time of her murder, was being raised by an aunt in philadelphia. but his mother was never far from his mind.
>> we used to have a debate about who loved each other more, you know, i love you more, no, i love you more. no, i love you more. and sometimes i even go to sleep and i still say it, like, mom i love you more, you know, it's -- that's the kind of stuff a kid never forgets. ever.
>> he also stayed in touch with marie 's husband, andre jackson. you still felt a connection to him.
>> yes. he was my dad. you know, that was the only father i had, and i missed him.
>> meanwhile, the rest of marie 's family wondered if andre knew more about her death than he was saying. they believed police had those same questions. but andre had never been arrested. and then came that letter, which changed everything. handwritten or typed?
>> it was typed.
>> the unsigned letter read in part, "it is very unlikely that the individual or individuals responsible for her death will be brought to justice. who you may be receiving lip service from her former office, believe me when i tell you that the agency has literally placed her death on the back burner." the agency, of course, meant marie 's secret employer, the central intelligence agency .
>> she worked for them, and they never offered a reward for her, any information regarding her case or anything.
>> the letter continued, "her former colleagues at work have been placed under a gag order by their office. they have ordered these people to cease all contact with you and marie 's family in pennsylvania. someone in your family needs to stir the pot."
>> we didn't know where the letter came from because it was anonymous and because she worked for the cia, so it opened up that door of suspicion that maybe they had something to do with it as well.
>> remember, when marie first disappeared, the fbi investigated on the theory it might have been espionage. but the family didn't know the result of that investigation and didn't know why police hadn't moved against andre .
>> and since we didn't have the answers, it was always a wonderment to us on why it was taking so long. maybe they all were working in cahoots with each other.
>> despite their dark suspicions, the family turned the letter over to inglewood police, but still, no answers. not for years.
>> i constantly called california to find out what was being done and what was happening with the case.
>> you didn't want to give up.
>> i couldn't give up. it was my sister.
>> the family didn't know it, but there was someone else who refused to give up. fbi agent rick hadel. he had never found any evidence of espionage in marie 's murder, but he'd also never forgotten about her.
>> so, here it is now january, 2002 , i'm a squad supervisor now, i'm the guy that assigns the cases instead of investigating them. and i'm talking with an agent. i said, tony, how about reopening this case as an assault on a federal officer case.
>> all just because you never stopped thinking about it.
>> exactly. i just -- i didn't like the -- the fact that you got a woman who has given her life, dedicated to the government murdered and just lying out there because nobody cares . and so i thought, well, let's give it another shot.
>> so, eight years after the murder, fbi agent tony vasley called on inglewood pd and met detective russ inard who was a month shy of retiring. they started combing through the old files and were assisted by a new inglewood detective steve siler.
>> technology advances so quickly that in 2002 i said to tony vasley, hey, maybe there's fingernail scrapings, maybe there's something of that nature.
>> in fact, there were fingernail scrapings in this case. there was also a drop of blood on marie 's saab, but at the time of marie 's murder, dna analysis was still in its infancy. those samples had never been tested. in 2004 , detective siler called john lewin , a prosecutor with the l.a. da's office major crime division. lewin specializes in cold cases .
>> they collected the fingernail scrapings and the blood and the detective had been unable to get the lab to test it, so when i first got on the case, i started trying to cash in favors with the crime lab to get it done.
>> but a ten-year-old cold case was not a priority. three more years passed. before those samples were tested. finally in november, 2007 , the fbi crime lab came through.
>> what we got was the information that would break this case wide open .