Several Democratic lawmakers who have sponsored bills to repeal or modify the Stand Your Ground law joined Sybrina Fulton at a news conference in Tallahassee, The Miami Herald reported. The legislation is believed to have little chance of support from the Republican majority.
Fulton wept as she addressed reporters.
"How many times are we going to bury our loved ones and not do something about it? We need to get rid of the law," Fulton said.
Martin, 17, was walking through a gated community in Sanford while returning to a relative's house when he was spotted by George Zimmerman, a neighborhood watch volunteer. Zimmerman continued to follow Martin after a police dispatcher suggested he back off.
Zimmerman says the unarmed Martin attacked him. He has been charged with second-degree murder.
Supporters of the Stand Your Ground law say citizens have the right to self-defense with proportionate force in public places as well as in their homes. Critics say the law justifies needless killing.
"These tragedies renew the argument that Stand Your Ground laws make ordinary citizens feel empowered to shoot first and ask questions later," said state Rep. Alan Williams, a Tallahassee Democrat. "We owe to not only Trayvon's mother, who's here with us today, but we owe it to future generations, we owe it to the citizens of the state of Florida, to ensure that these laws will not bring harm to their families or to our streets."