Jail or Canada? Malcolm Watson chose Canada.

In an unusual sentence that has immigration lawyers questioning its legality, the U.S. citizen has agreed to stay out of the United States for the next three years as punishment for having sex with a 15-year-old female student.

The exile starts Monday for the 35-year-old former Buffalo Seminary teacher, who was arrested in April after a mall security guard noticed him and the girl sitting in a parked car for two hours.

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Erie County District Attorney Frank Clark called the plea deal "a little dicey" but said the girl's family was happy with it.

Under the sentence for sexual abuse imposed by Cheektowaga Town Court, Watson can enter the United States only to report to his probation officer. Watson already lives across the border in Fort Erie, Ontario, with his Canadian wife and three children.

But exiling a citizen is unheard of, said Robert Kolken, a Buffalo immigration lawyer.

"I don't see how a judge sitting in a criminal court in the U.S can lawfully banish a citizen as a condition of sentencing," he said.

Cheektowaga Justice Thomas Kolbert could not be reached for comment.

Another immigration lawyer, Robert Berger, warned that Watson could be barred from entering Canada because of his new criminal record.

Even Watson's lawyer, Oscar Smukler, said he was surprised by the deal.

"We did some research on the question of whether Canada might consider throwing [Watson] out, which would make him a man without a country," Smukler said.

The alternative sentence? As much as a year behind bars.

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