Clint Eastwood's Oscar-nominated drama American Sniper may have taken $150 million to date at the box-office, though the wife of Chris Kyle - the movie's subject - is facing a bill of nearly $1.345 million for "unjust enrichment" of her late husband's multi-million dollar estate.

American SniperBradley Cooper plays Chris Kyle in Clint Eastwood's Oscar-nomnated drama

Played by Sienna Miller in the movie, Taya Kyle has been left with the lofty bill after a court granted it to Jesse Ventura - a former governor of Minnesota and professional wrestler - in a defamation case.

Mr Kyle - known as the most lethal sniper in U.S. military history - claimed that he beat up Mr Ventura at a gathering of former Navy Seals after the former politician said that American soldiers deserved to die in Iraq. Mr Ventura went to court to clear his name after insisting that he no such incident occurred - the jury agreed.

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Jurors awarded Mr Ventura in $500,000 in damages for statements "with actual malice" and another $1.345 million for unjust enrichment after concluding that Mr Kyle's estate profited from defaming Ventura through the success of his memoir American Sniper, which spent 37 weeks on the New York Times Bestsellers List.

Mr Kyle was shot dead in 2013 by a troubled soldier at a Texan gun-range, though Ventura pursued the case and claimed publisher HarperCollins would pay the damages through libel insurance. Still, Mrs Kyle's lawyers have launched an appeal after a judge rejected an earlier request to overturn the verdict.

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As the Telegraph notes, the case potentially fuels doubt about Kyle's credibility. The Pentagon has confirmed he made 160 kills during his four tours of Iraq, though some of his other stories are unverifiable, including one anecdote in which he claimed to have shot dead two car-jackers at a petrol station near Dallas.

He also claimed he was hired to travel to New Orleans amid the chaos after Hurricane Katrina and shot dead around 30 armed looters from a perch on top of the Superdome stadium. 

Neither story was confirmed by police or officials. 

More: read our full review of American Sniper