A memorial for Michael Brown in Ferguson, Mo. (Jeff Roberson/AP)

The grand jury considering whether to indict the Ferguson, Mo., police officer who shot and killed Michael Brown could come to a decision by November, St. Louis County Prosecutor Bob McCulloch said Wednesday.

Jurors have received an extension that allows them to consider the case until early January, which means the decision on Darren Wilson could come nearly five months after Brown was killed. But the jury will not need that much time, according to McCulloch.

“Initially, when we first start presenting we said mid-October, which was a pretty aspirational date,” he told The Washington Post on Wednesday. “Now, it is looking like very late October, probably going into the first or second week of November even.”

McCulloch had originally said it would take until October to present all of the evidence to the grand jury, which is only hearing evidence related to the shooting. It was announced last week that the jury’s deadline had been pushed back to Jan. 7.

The entire grand jury process is taking longer because of the way evidence is being presented to jurors, he said. McCulloch’s office is taking an unusual approach with this grand jury. Rather than waiting for the police investigation to wrap up, evidence is being presented to jurors as it arrives.

“It’s gone slower than I anticipated,” he said Wednesday. “The witnesses have taken longer than we thought they would.”

He said in some cases, witnesses have given statements to the media, the FBI and county police. Each of those are being presented to the grand jury. In addition, as witnesses are testifying, jurors are asking a number of questions.

The standing St. Louis County grand jury was originally going to be in session until September, but the term was extended just for this case. The grand jury consists of one black man, two black women, six white men and three white women.

McCulloch said during an interview Wednesday morning with the St. Louis radio station 550-KTRS that the January extention stemmed from “an abundance of caution,” but he also said nobody expects the jurors will need that long.

This timeframe and the unusual process both stem from the magnitude of the case being considered by jurors, he said during the radio interview.

“There’s an enormous amount of evidence that is being presented to the grand jury that, in most cases, wouldn’t happen,” McCulloch said. “But because this case is so significant, in our community certainly, there are a lot more people coming in to testify than there would otherwise be.”

Protesters and elected leaders have called on McCulloch to be replaced by a special prosecutor, pointing to his personal history. One such protest resulted in multiple arrests earlier this month. McCulloch has repeatedly declined to step aside and has said he is “fair and impartial.”

It is unclear what will ultimately happen with the grand jury. Wilson could be charged with murder or manslaughter, or he could avoid indictment altogether.

The grand jury’s decision could set off another series of protests and confrontations between police and residents in the Ferguson area. Even though the nightly clashes between residents and militarized police officers following Brown’s death have subsided, turmoil still exists in the region.

This was evident in the events that unfolded the day before McCulloch’s radio interview. Police and protesters faced off in the streets on Tuesday night, several hours after a memorial for Michael Brown was destroyed in a fire, in a scene that evoked the heated situation last month. Two police officers suffered minor injuries in the fray, and five people were arrested.

This post has been updated. Last update: 4:24 p.m.