JACKSONVILLE, Fla. -

The Senate's "stand your ground" hearing that was scheduled for Tuesday has been postponed due to the Navy Yard shooting that took place in Washington D.C. on Monday.

The mothers of Trayvon Martin and Jordan Davis were scheduled to take the stand. They will testify together at the Senate's hearing at Capitol Hill.

Davis died in November in what police say was an argument over loud music at a Southside gas station. The suspect in that case, Michael Dunn, is expected to use stand your ground as a defense.

In Martin's case, his killer George Zimmerman ended up using self-defense in his trial for Martin's killing, but did not cite the controversial law. He was acquitted in the summer of 2013. Davis and Martin's mothers have been pushing to change the law since.

This isn't the first time these two mothers have gotten together, and this time they'll be joined by multiple attorneys and crime prevention leaders.

"From the trial, you've seen my son wasn't doing anything wrong," said Sybrina Fulton, Martin's mom. "Trayvon was simply walking home and he didn't have a weapon, he didn't have a gun, he had candy and a drink. So we need to take a look at that. He wasn't a suspect, he wasn't a burglar, he was just minding his own business going home. But it was somebody else's perception of him that changed everything, that caused his death."

Dunn's trial is set to begin in early 2014. He says he thought he saw a gun in the SUV that Davis and other friends were in, but police said no weapon was found in or around the vehicle. A few attorneys and leaders of crime prevention groups will join the two mothers Tuesday morning in Washington, as they all plan to voice their concern and ask senators tough questions.

"It's not a black-white issue. It's a national issue. There needs to be an amendment to the stand your ground law and protect yourself," Fulton said.

The new date of the hearing has not yet been set.