Trayvon Martin's dad calls his son "my hero" Martin's parents say "something wasn't right" from the beginning of the investigation The outcry is making the job difficult, the prosecutor says (CNN) -- The parents of Trayvon Martin, the unarmed black teen killed by a Hispanic man who claims self-defense, said Wednesday they have faith in authorities investigating the case. "I feel confident that they're going to do a thorough investigation," Sybrina Fulton, Martin's mother, told CNN. We're trying to be patient, even though it's been over a month. We're trying to be patient, and we're trying to press on for justice. Fulton said she and Martin's father, Tracy, are not only speaking for their son, but for others who have died from violence. Tracy Martin shared memories of the son he called "my hero," who dreamed of being an aviation mechanic and wanted to make his family proud. The 17-year-old was shot to death February 26 by George Zimmerman, a neighborhood watch volunteer, as Martin was walking back to his father's fiancee's house in Sanford, Florida. He was wearing a hoodie and carrying Skittles candy and a can of iced tea he had purchased from a nearby convenience store. Zimmerman says he killed Martin in self-defense after the teen attacked him in the gated community. He had called police to report a suspicious person and said he was following Martin, despite being told by a dispatcher he didn't need to do so. Zimmerman has been questioned but not charged, police said, because they lacked evidence to contradict his account. ABC News reported Wednesday, citing multiple sources, that the lead investigator in the case recommended Zimmerman be charged with manslaughter after the shooting, but the state attorney's office determined there was not enough evidence to lead to a conviction. Asked about the ABC News information Wednesday, Tracy Martin said it was "heart-wrenching." "That just lets me know from the onset that something wasn't right about the investigation," he said. The initial police report from the incident lists the alleged offense as "homicide/negligent" and "manslaughter/unnecessary killing to prevent unlawful act." And the Seminole County state attorney's office has said previously that evidence obtained by police was insufficient for an arrest. Tracy Martin said he has many questions for investigators. "All I know is that my son was carried away in a body bag, and Zimmerman was left to go and shower and sleep in his bed," he said. Tracy Martin told CNN's "AC360" Tuesday night he believes Zimmerman racially profiled his son. "And then, even worse, I think the police profiled Trayvon Martin," he said. However, there also is support for Zimmerman from an unlikely source: an African-American friend who says he has endured his share of racial discrimination. On Tuesday, Joe Oliver -- a former CNN anchor who now works at WESH-TV in Orlando -- defended his friend, saying Zimmerman is no racist. Tracy Martin said Wednesday the 911 tape shows Zimmerman was profiling his son. "Maybe (Zimmerman) wasn't a racist to (Oliver) while they sat around and talked, but clearly, on the tape, he was profiling my son, and that leads me to believe that (Zimmerman), in fact, was a racist," he said. In a recording of Zimmerman's call to police, some people have said they hear what sounds like a possible racial slur. Angela Corey, a special prosecutor assigned to investigate the case, said Tuesday investigators would look into the allegations Zimmerman used a racial slur. Martin, who lived in Miami, was visiting Sanford after receiving a 10-day suspension from school, a family spokesman has said. An empty plastic bag found in his book bag was determined to contain marijuana residue. Benjamin Crump, Martin's parents' attorney, said information regarding the suspension was irrelevant and amounts to a smear campaign against the youth. Corey said Tuesday the "political outcry" is making her job difficult. "Any time there is a misunderstanding of the process, based on what we are required to do under Florida law, it does make our job more difficult," she said. Florida's law allows the use of deadly force anywhere a person feels a reasonable fear of death or serious injury. It has been cited in a number of justifiable homicide cases in Florida. There are 911 calls with neighbors saying they heard screams -- though it isn't clear whether they came from Zimmerman or Martin. According to the version of events police apparently gave to Martin's parents, after Zimmerman got out of his car, Martin approached him and asked "did he have a problem," Fulton said. Fulton said police told her Zimmerman was reaching into his pocket for a cell phone when Martin punched him and a scuffle ensued. But, she said, she does not believe that account. "Knowing Trayvon -- those are not the words of Trayvon," she said. Crump has said the teen's girlfriend was on the phone with him just before the shooting and that what she heard "completely blows Zimmerman's absurd self-defense claim out of the water." While authorities continue to sort out the facts, coast-to-coast protests have taken place almost daily in recent days, with the hoodie becoming a symbol of the public outcry. I can't believe in our day and time people are still perceiving our youth as troublemakers. ... Terrence Robinson attended a pair of rallies over the weekend in Chicago, wearing a plain gray hoodie. "The reason I marched for Trayvon Martin was because I was tired of seeing young black men like myself -- and all youth for that matter -- being gunned down due to senseless violence," he said. Tracy Martin declared that "everyone's trying to turn the focus on George Zimmerman and make George Zimmerman the victim. "We have a dead 17-year-old son," he said. CNN's Umaro Djau, Ed Payne and Tracy Sabo contributed to this report.