SANFORD, Florida (CNN) -- Special prosecutor Angela Corey has decided against using a grand jury in the case involving the shooting death of 17-year-old Trayvon Martin, her office said Monday.
The grand jury, set to convene Tuesday, was "previously scheduled by the former prosecutor," said the statement from Corey.
"The decision should not be considered a factor in the final determination of the case," her office said.
Corey said the investigation into the case continues. The state attorney has maintained that a grand jury is not needed to file possible criminal charges against George Zimmerman, the neighborhood watch volunteer who killed the teen February 26.
The case has triggered a nationwide debate about Florida's "stand your ground" law -- which allows people to use deadly force anywhere they feel a reasonable threat of death or serious injury -- and race in America.
Prosecutors are trying to unravel what happened the night Martin was killed. Witnesses and attorneys for both sides have offered conflicting accounts. Two prosecutors are working to determine whether there is sufficient evidence to bring charges against Zimmerman, 28.
"We had hoped she had enough evidence without the need to convene a grand jury," said Benjamin Crump, attorney for Martin's family. "The family is trying to have patience and faith through all of this."
Crump said the family is hoping for charges against Zimmerman and an arrest as soon as possible.
"We want a very public trial so the evidence can come out and show people that the justice system works for everybody," he said.
Zimmerman's attorney, Hal Uhrig, texted his reaction to CNN's Martin Savidge: "Not surprised. Don't know what her decision will be. Courageous move on her part."
Thousands have converged on Sanford to join in protests calling for Zimmerman's arrest and criticize the police department's handling of the case.
On Monday, a group of students calling themselves the Dream Defenders marched to the Sanford police station, singing and carrying a banner saying, "We are Trayvon Martin." The march began Friday in Daytona Beach, about 40 miles away, and continued through the weekend.
The marchers linked arms, sang and chanted as they faced the building's entrance Monday. Six of the demonstrators, wearing hoodies, were blocking the department's main entrance. Martin was wearing a hoodie when he was killed.
The Sanford Police Department said in a statement its office was "temporarily closed to the public ... due to the actions of student protestors. The students are currently occupying the space in front of the police department blocking the main entrance." The protest will not affect police and fire response to emergency calls, the department said.
"The city of Sanford hopes the actions of the students will be as peaceful and orderly as the previous rallies and marches have been," City Manager Norton Bonaparte Jr. said.
Corey said previously she has never used a grand jury to decide on charges in a justifiable homicide case.
"We do a thorough investigation. We make that decision ourselves," she said.
Sunny Hostin, legal analyst for CNN sister network HLN, said she was not surprised by Corey's decision.
"As a former prosecutor, I typically made my own charging decisions," she said. "... Many, many seasoned prosecutors use their judgment and make charging decisions, don't necessarily punt the ball to lay people, to a grand jury."
Corey's decision was "the smart thing to do," she said. "... Now Angela Corey is letting everyone know that this is her case. This is her decision."
Although details of the incident remain murky, what is known is that Martin ventured out from his father's fiancee's home in Sanford to get a snack at a nearby convenience store. As he walked home with a bag of Skittles and an Arizona iced tea, he was shot and killed by Zimmerman.
Sanford police questioned Zimmerman and released him without charges.
From there, the case has evolved into opposing allegations from Zimmerman's supporters, Martin's family and authorities.
Zimmerman says he killed Martin in self-defense after the teen punched him and slammed his head on the sidewalk, according to an Orlando Sentinel report that was later confirmed by Sanford police.
One of the responding officers saw a wound on the back of Zimmerman's head and a bloody nose, and noted that his back was wet -- indicating he had been lying in the grass, according to the police report.
An enhanced copy of a surveillance video showing him in police custody after the shooting appears to show a bump, mark or injury on his head.
Martin's family and supporters have dismissed the video.
They say Zimmerman, who is Hispanic, racially profiled the teen, who was black, and ignored a police dispatcher's directive not to follow him.
Zimmerman's attorneys interpret the call differently, and say the operator did not order Zimmerman not to follow Martin.
A recording of a 911 call made the night of the shooting