A California mom says her public school administrators violated her daughter's First Amendment rights when they ordered the sixth-grader to take off her pro-life T-shirt.

Anna Amador has gone to court on behalf of her daughter, who she says was ordered by her principal to change her shirt on "National Pro-Life T-Shirt Day." The shirt the 12-year-old was wearing displayed two graphic pictures of a fetus growing in the womb.

The incident occurred in April 2008 at McSwain Elementary School, a K-8 school in Merced, Calif. Amador alleges in her legal complaint that school Principal Terrie Rohrer, Assistant Principal C.W. Smith and office clerk Martha Hernandez mistreated her daughter and denied the girl her First Amendment rights when they ordered her to leave the cafeteria and change her shirt.

"Before Plaintiff could eat [breakfast] she was ordered by a school staff member to throw her food out and report immediately to Defendant Smith's office, located in the main office of McSwain Elementary School," the complaint reads.

"Upon arriving at the main office, Defendant Hernandez, intentionally and without Plaintiff's consent, grabbed Plaintiff's arm and forcibly escorted her toward Smith's office, at all times maintaining a vice-like grip on Plaintiff's arm. Hernandez only released Plaintiff's arm after physically locating her in front of Smith and Defendant Rohrer...

"Smith and Rohrer ordered Plaintiff to remove her pro-life T-shirt and instructed Plaintiff to never wear her pro-life T-shirt at McSwain Elementary School ever again...

"Completely humiliated and held out for ridicule, Plaintiff complied with Defendants' directives and removed her pro-life T-shirt, whereupon, Defendants seized and confiscated it. Defendants did not return Plaintiff's property until the end of the school day."

The school administrators dispute some of the allegations, said Anthony N. DeMaria, attorney for the McSwain Union Elementary School District.

"I think the school district has a very strong defense," DeMaria said. "The complaint does not properly characterize the events that happened. Certainly we dispute some of the events."

He said he was unable to reach the administrators to determine which parts they say are incorrect, because school is out for the summer. Rohrer, the principal, told FOXNews.com on Monday that she could not issue a statement without consulting with the school superintendent and their attorney. The other defendants and school district employees did not respond to calls and e-mails from FOXNews.com.

The school district sought to get the case thrown out due to "failure to state a cognizable claim," but a U.S. Eastern District Court judge ruled last month that all but one of Amador's claims could go forward.

The complaint quotes school district officials saying that they ordered Amador's daughter to remove the shirt because it constituted "inappropriate subject matter" in violation of the school's dress code, which bans clothing with "suggestion of tobacco, drug or alcohol use, sexual promiscuity, profanity, vulgarity, or other inappropriate subject matter."

Amador claims in the legal complaint that other students at the school have been allowed to wear expressive shirts, and she blames the school for “inconsistently applying their Dress Code based upon subjective determinations as to which messages are acceptable and which messages are not.”

One of the girl's lawyers, Mark A. Thiel, said that the images on her shirt of a fetus in the womb were same as those in her science textbooks. He said no student had complained about the shirt, and he said the girl's parents were not called when the incident took place.

"This was a young girl, not even in high school. But they didn't call," he said.

A spokeswoman for the local Planned Parenthood chapter declined to take sides in the case.

"Even offensive speech is protected as long as it doesn’t impinge upon the rights of others," said Deborah Ortiz, vice president of public affairs for Planned Parenthood Mar Monte.

"School administrators have a mission to educate, and the student’s right to political speech should be protected in balance with this education mission."

UCLA law professor and First Amendment expert Eugene Volokh said Supreme Court precedent appears to support the girl's case.

"During the Vietnam War, the Supreme Court ruled that wearing black arm bands [at school, to protest the war] was OK,” Volokh said. “If students can wear armbands in protest, why can't they wear a pro-life shirt?"

He said the case would be different if there was evidence that the shirt could have led to disruption or fighting.

"Schools have a lot more authority than the government does in regulating speech,” he said. “If someone is speaking on a street corner and it looks like other people are going to start a fight over it, the government's job is to protect the speaker. That is not the case in schools. We need to make sure students learn. So if speech is highly disruptive, well … in that case we can suppress it.

"But the school's position that they can restrict speech just because they find it inappropriate is not correct."

But the fact that it's a K-8 school with very young children could change things, said Brooklyn Law School professor William Araiza. He pointed to the 2007 Supreme Court decision in Morse v. Frederick, where the court allowed a high school to suspend students in Juneau, Alaska, who waved a banner that read “Bong hits 4 Jesus” from across the street during an Olympic torch relay, because it was seen as promoting illegal drug use.

“[The school] could almost use a “bong hits” kind of rationale about protecting students from inappropriate messages,” Araiza said. “For instance, would you allow a 4th grader to wear a gruesome picture of a bomb scene? You probably wouldn't.”

First Amendment attorney William Becker, who represents Amador, disagreed that the shirt could be seen as containing inappropriate messages.

"The message of the T-shirt is that life is sacred," he said. "One would be very hard pressed to find anything wrong with that particular idea, except that some people do object to the political message.”