We are presumed innocent until proven guilty in this country. We are guaranteed a fair trial by an impartial jury. That’s the bedrock of our justice system.

But what about the high-profile defendant who lives through months and sometimes years of sensational media coverage before his or her case comes to trial? The potential jury pool in their community can become saturated with negative news about the accused, leaving people to justifiably ask how in the world a fair trial can be conducted.

The upcoming capital murder case of 25-year-old Casey Anthony of Orlando, Fla., makes my point. Now, she might well be the cold-blooded killer of her 2-year-old daughter, Caylee, whom she had lost track of for more than a month before police were notified. But what if she isn’t?

Almost every week for nearly three years — sometimes every day — local TV and radio stations have been running stories about the so-called “Tot Mom.” Newspapers all across the state have covered the case constantly. And the disappearance of Caylee captivated a national audience, as well, when cable TV talk shows dedicated to crime took notice.

Since July 2008, potential jurors in Florida have consistently heard the words “Casey Anthony” and “murder” in the same breath. It’s not beyond belief that a permanent and horrible image of the defendant is already burned into the collective psyche.

Among the media’s revelations: Dozens of racy photographs of the young single mother drinking and partying during the month she said her daughter was missing. Casey’s claims of a kidnapping nanny named Zanny were found to be completely false by detectives who concluded no such person existed. Anthony’s abandoned car was picked up by her father at a tow lot, and both her parents described it as smelling like there had been “a dead body inside.” During the long search for her missing child, Anthony was charged with forging checks she had stolen from friends and family. And it turned out that the job at Universal Studios she had bragged about for years never actually existed.

In December 2008, six months after Caylee was reported missing — not by her mother but by her grandmother — the child’s remains were found with a remnant of a Winnie the Pooh blanket and with layers of duct tape wrapped around her head, covering her tiny nose and mouth. A crime scene report revealed a smiley sticker had been placed over the child’s lips. Crime pundits on television speculated these kinds of loving gestures must have come from someone close to the girl and were not the hallmark of a stranger murder.

The anti-Anthony revelations piled up as the days wore on. Most disturbing was video of the elder Anthonys fending off groups of screaming protesters outside their home. They hurled curses at the baby’s grandparents, and at one point a small child appeared holding a sign reading, “Will you kill me, too?”

It would be easy to blame the media for the tone surrounding this case, but that’s not fair.

Florida has the most liberal sunshine laws in the country, which means that whenever the police or prosecution developed information about Anthony — from detective interviews with witnesses to videotaped prison visitations she had with her parents — it was promptly released to the public. The media wouldn’t have been doing their job if they hadn’t reported this information.

Transparency of government is a positive thing, generally speaking, but we can’t forget there are pitfalls, too.

Anthony’s defense team asked Superior Court Judge Belvin Perry to move the trial out of Orlando in an attempt to mitigate all the pre-trial publicity. Judge Perry refused the request — but, oddly, he agreed to try to choose a jury from an outside county. Once chosen, these jurors would be bussed back to Orlando and sequestered in hotels for what’s expected to be a two- to three-month trial.

It is rare to sequester a jury for the entire length of a trial because it takes such an emotional toll. It seems like a double whammy for this defendant. Think about it. The jurors will be plucked away from everything familiar — work, friends and family — and they will be held in near isolation. They won’t be allowed television, radio, newspapers or Internet. They won’t be allowed to speak to anyone, and there will be no unescorted exercise or walks around the block.

The group may have to change hotels if those determined protesters calling for Anthony’s conviction show up.

Above all this, jurors will take on one of the toughest assignments a citizen can perform: They’ll be asked to listen to a murder case, to view gruesome crime scene and autopsy photos of a little girl. And at the end, they will have to make a life-or-death decision.

Can they really be impartial? Will they be able to focus while enduring the hardships of sequestration? Can there be a fair trial here?

I’ll be in Florida covering this case. I’ll let you know what I discover.

Diane Dimond is the author of Cirque Du Salahi: Be Careful Who You Trust. Click here for more information. She can be contacted at diane@dianedimond.net.