Heather Ellis, now a 24-year-old schoolteacher, is on trial on felony charges this week in Dunklin County, Missouri.

Kennett, Missouri (CNN) -- This much isn't in dispute: Heather Ellis cut in line at a Wal-Mart nearly three years ago.

But the accounts of what happened next vary, depending on whom you ask -- and has divided this economically struggling Missouri town of 11,000 along racial lines.

Ellis, then a college student with no criminal history, said some white patrons shoved and hurled racial slurs at her when she switched checkout lines at Wal-Mart in January 2007.

Store employees refused to give her back her change and called police, she said.

And when she was taken outside to the parking lot, an officer allegedly told her to "Go back to the ghetto." Another roughed her up, she said.

Witnesses and police offer a different take: Ellis was belligerent, shoving merchandise belonging to another customer to make way for hers on the conveyor belt, kicking one officer in the shin and splitting another's lip.

A Dunklin County Circuit Court jury heard from the prosecution and defense as Ellis' felony trial got under way Wednesday

Ellis -- who is charged with assaulting police officers, resisting arrest and disturbing the peace -- could face up to 15 years in prison if convicted.

A verdict could come as early as Thursday.

Officials with the American Civil Liberties Union and Southern Christian Leadership Conference said the case is indicative of racial bias in the town, where 13 percent of the population is African-American.

Kennett, the hometown of singer Sheryl Crow in the southeastern corner of Missouri, has struggled economically.

Black and Hispanic residents have long complained about the predominantly white police department unfairly profiling them during traffic stops.

When Ellis' supporters held a peaceful rally in June, officers found business cards scattered along the route that read: "You have been paid a social visit by the Knights of the Ku Klux Klan. The next visit will not be social."

During another rally Monday, a handful of opponents stood on the sidelines waving Confederate flags.

"I know it's racism. It's blatant, overt racism," said Ellis' father, the Rev. Nathaniel Ellis.

Her attorney, however, has not brought up race as a contributing factor in the case.

"I'm not going to go there," Scott Rosenblum said. "It's up to the prosecutor to decide to prosecute the case that the police investigate and present to them."

At the time, Ellis was a pre-med student at Xavier University in New Orleans, Louisiana.

She was home visiting relatives when she made a trip to Wal-Mart on January 6, 2007, to pick up some items for her mother. Ellis' 15-year-old cousin was with her.

After selecting their items, the two stood in different checkout lines. Noticing that her cousin's line was moving faster, Ellis cut in next to him, angering other customers.

In the arguments that followed, Ellis yelled so loudly that employees in the back of the store could hear her, prosecutor Morley Swingle said during his opening statements Wednesday.

Ellis "went ballistic in a profane tirade," he said.

When police arrived to remove her from the store, Ellis confronted them with the "worst kind of cussing imaginable," Swingle said.

"If you arrest me, I will kick your [expletive]," Ellis told one officer, according to the prosecutor.

She repeatedly kicked one officer in the shin and another in the face, police said.

"I ain't going nowhere until I get my [expletive] change back," Ellis told officers, according to a police incident report.

"She resisted arrest, kicked her feet and stiffened her body" when officers tried to put her in the police cruiser, the report said.

Customer Teresa Kinder testified that Ellis shoved her items back on the checkout conveyor belt to make room for her own. When Kinder protested, Ellis allegedly threatened her with violence.

For his part, defense attorney Rosenblum described the incident as an unjustified assault on his client.

When Ellis tried to seek help from the cashier and a store manager during the arguments, "her voice was not heard," he said.

Store employees treated Ellis with indifference, Rosenblum said, and officers taunted her by asking her to "Go back to the ghetto."

Ellis told the ACLU that officers addressed her "with a series of racial remarks that included the N-word and everything you can imagine."

She said the Wal-Mart cashier asked for her ID card, even though she was paying in cash, and refused to give back her change.

Five store cameras apparently captured Ellis' movements from the checkout line to the parking lot, where the alleged physical confrontation with police took place. But the store has not made the tapes public.

An ACLU official who viewed the footage called it "inconclusive." It captures the incident from one angle and shows a mass of people moving toward the police car after the initial confrontation, which wasn't caught on tape.

"When you read the probable cause affidavit here, quite frankly, it does sound like she's out of control," legal analyst Lisa Bloom said. "There are five police officers. They're all saying the same thing. There are at least four other witnesses within the Wal-Mart store. They're all saying the same thing.

"She has a completely different version of the facts," Bloom added. "She feels that she was treated differently; it was on account of her race. It's in a racially charged community. And these charges are being blown out of proportion, so she's facing 15 years behind bars for an incident that began with cutting in line. ... I think there's good reason to think there are some racial allegations here."

Now a 24-year-old schoolteacher, Ellis is engaged to a state trooper. She has not spoken publicly to reporters about her case, saying she has been instructed not to do so.

"I wish I could, but I can't," she said leaving the courtroom Wednesday.

Two years ago, prosecutors offered a plea deal under which she would receive probation if she dropped her complaint against the police.

"She decided not to sign it, because she was taught to never admit guilt when you're innocent," her father said. "We plan to fight it as we have. We're marching on."