Wendy Brown had the mini-skirt, the pom-poms, and the pool party lifestyle. As far as her teachers were concerned, she was an all-American cheerleader. There was only one small problem: she was 20 years too old to be in high school.

In fact, the 34-year-old fraudster was old enough to have a teenage daughter of her own. The girl lived in another state, and it was her identity that the mother stole to fool the education authorities in the town of Ashwaubenon, Wisconsin (population: 17,000).

Perhaps too embarrassed to question her unusually mature looks and figure, the teachers at Ashwaubenon High allowed Brown to take part in classes, join the cheerleading squad, and attend social events. They even gave her a cheerleader’s locker.

Brown’s scheme collapsed only when she failed to turn up to school one day last August. Suspecting that something was amiss, truancy officers investigated, and were astonished by what they found: the “cheerleader” was locked up in a local jail, where she was being held pending unrelated fraud charges.

Yesterday Brown was committed to three years in a psychiatric unit after a court found her not guilty of identity theft because of “mental impairment”. She was also ordered to spend three years on probation for the unrelated fraud, which involved her stealing $759 from a prospective tenant of an apartment from which she had recently beeen evicted.

According to court documents, Brown told police that “she wanted to get her high school degree and be a cheerleader because she had no childhood, and was trying to regain a part of her life she missed”. “I made a mistake,” she told the court.

The police remain sceptical that this was the real motive, pointing to her long history of deception. “Ms Brown’s criminal history says she’s been involved in fraud and deceptive practices across the country for most of her adult life,” said Lieutenant Jody Crocker, an Ashwaubenon Public Safety officer. “It comes to no surprise to us that she was able to pull something like this off.

“I can only guess, if history repeats itself, that her motive has something to do with money. Unless we take it at face value that she wanted to go and relive her childhood. I personally don’t buy that.” The judge in Brown’s case, Sue Bischel, said she agreed with a psychiatrist’s recommendation that the woman neeeded “intensive counseling and treatment that she’s not going to get and would have a difficult time getting in the community”.

The psychiatrist had told the court that Brown suffered from bipolar and borderline personality disorder, resulting in delusional mental illness, and could not understand why her behaviour was wrong.

The prosecutor in the case, Deputy District Attorney John Luetscher, disagreed. He argued that Brown was “a straight-out con artist”.

Fellow cheerleaders said they noticed that the 34-year-old was unusually mature-looking. They had dismissed any suspicions, however, because the fraudster had acted so convincingly like a teenager.

“She did look a little older, but you didn’t want to question it,” said Spencer Corpus, a student at Ashwaubenon, in a CBS News interview. “You just go, Aw, alright, whatever’.”

Another student, Hope Edlebeck, said: “I thought it was really bizarre. It’s just something you never hear. A 34-year-old going to school.”

Some residents of Ashwaubenon were outraged, however, that the school authorities allowed themselves to be taken in. “I believe the entire staff of Ashwaubenon High should be drug tested for this completely inexcusable incident,” wrote one, on the website of a local newspaper, the Green Bay Press Gazette.

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