Martin's parents spoke briefly Tuesday at a Capitol Hill forum that began with a moment of silence for their son, who was shot and killed Feb. 26 in a gated Florida community.
Martin's father, Tracy Martin, thanked "everyone who is holding the legacy of Trayvon" while his mother, Sybrina Fulton, said, "Trayvon was our son, but Trayvon is your son."
Some members of Congress have called for a hate crimes investigation. The Justice Department has told Martin's parents that getting hate crime charges will be a challenge.
The admitted shooter, George Zimmerman, has said he acted in self-defense. He has not been arrested or charged.
ABC News confirmed through multiple sources Tuesday that the night Trayvon Martin was shot, Chris Serino, the lead homicide detective on the case, said he "disbelieved" George Zimmerman's testimony and recommended in an affidavit that he be arrested for manslaughter.
However, the state attorney's office instructed Serino not to press charges because it was deemed there wasn't enough evidence to lead to a conviction.
Meanwhile, Martin, 17, reportedly had some disciplinary issues at school the same week he was killed in Sanford, Fla., by Zimmerman. Martin was suspended from school for having a baggie with marijuana residue in his backpack and for graffiti, according to ABC News.
Zimmerman said he acted in self-defense after Martin punched him and tried to grab his gun.
"George felt like and believed with all his heart he had to make a decision to defend himself and to save his life," said Joe Oliver, Zimmerman's friend.
A 13-year-old witness told ABC News that he saw Martin on top of Zimmerman and that the man being attacked was wearing a red T-shirt, which was the same colored shirt Zimmerman had on. Initial reports also show Zimmerman suffered a broken nose.
Martin's parents have been on the defensive, saying the police are leaking information and trying to ruin their son's reputation.
"It tears me apart to sit here and listen to the slander that they're giving to my son," said Martin's father, Tracy.
The Martins met with prosecutors Monday, and in light of all these new details, authorities are now planning to re-interview everyone involved in this case.
Emotions over the case have been running high across the country. Protesters planned to march to the White House Tuesday to demand a federal investigation into the incident.
On Monday night, more than 1,000 people turned out in downtown Los Angeles for a march and rally in honor of Martin.
The Associated Press contributed to this report.