(CBS News) After the jury of six women -- none of them black --of murder and manslaughter charges in the shooting of Trayvon Martin Saturday night, protesters took to the streets.
Many are demanding the Justice Department bring federal civil rights charges against Zimmerman.
Monday,only to "follow the facts and the law" while addressing one of America's oldest African-American sororities.
"The Justice Department shares you concern. I share your concern and as we first acknowledged last spring, we have opened an investigation into the matter," Holder said.
This case first came to national attention when the Sanford, Fla., police declined to arrest Zimmerman, believing the neighborhood watch volunteer shot Martin in self defense. Protesters at that time accused the police and Zimmerman of racial bias.
Even after the trial and the not-guilty verdict, Zimmerman's legal problems may not be over.
Trayvon Martin's parents are expected to file a civil suit against Zimmerman alleging wrongful death. He would have to testify.
CBS News sat down this afternoon with Angela Corey, the special prosecutor in the Zimmerman trial. While the jury was allowed to consider manslaughter, Corey has been criticized for focusing on a murder conviction for the entire trial.
CBS News: Did you overcharge with second-degree murder?
Angela Corey: I don't think that we overcharged. He killed a young man because he thought he was a criminal. And he should be held accountable for what he did.
CBS News: You wanted accountability. A manslaughter conviction would have put Zimmerman behind bars. So why not push harder for that?
Corey: In hindsight, that might have been something we should have done. We second guess ourselves on we win or don't win - "Gosh, I wish I had done a better job on this or that." It's hard to say what could have changed this verdict.
CBS News: Are you comfortable with George Zimmerman in particular getting his gun back?
Corey: I'm not comfortable with the way George Zimmerman went out in the night armed, looking for someone he believed is dangerous. If they're dangerous enough to call the police, don't get out of your car.
A White House spokesman said that President Obama would stay out of that Department of Justice investigation because it would be inappropriate for him to get involved.