A federal judge in Chicago is set to issue a verdict in a peculiar civil trial over a celebrated Scottish-born artist's insistence that he did not paint a landscape work which was once valued at more than 10 million US dollars (£7.6 million).

Some of Peter Doig's paintings have sold for more than 20 million dollars (£15.3 million), and the owner of the disputed picture, a prison official from Canada, sued in the US court for millions in damages after its projected sales price nosedived after 57-year-old Doig denied it was his work.

The owner, Robert Fletcher, of Ontario, Canada, maintains that the painting of a desert landscape with giant red rocks and a receding pond, which he paid 100 dollars for in the 1970s, is by Doig. If it is not, according to one filing by Mr Fletcher's lawyers, "it is essentially worthless".

Read more: Scots artist Peter Doig at centre of £3.8m court case to prove painting is not his work

Authenticity disputes typically arise long after an artist dies; not, as in this case, when the artist is still alive and flatly denies a work is his. The oddity of such a dispute making it all the way to trial has drawn the interest of the wider art world.

After a week of hearing evidence, US District Judge Gary Feinerman said he would announce his verdict on Tuesday. The lawsuit was filed in Chicago because one auctioneer who had expressed interest in selling the painting is based in the city.

Mr Fletcher contends he bought the painting from Doig around 1976 - when he says the Scottish artist was serving a jail sentence for possessing LSD in Canada's Thunder Bay Correctional Centre, where Mr Fletcher was employed. It was long after he bought it that a friend saw it at his home and said it appeared to be by an internationally acclaimed artist.

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Doig, who now lives in Trinidad, said he did not begin using the type of linen canvas the work in question is painted on until late 1979. He also told the court that he had never been imprisoned in Ontario or anywhere else in Canada.

Such a dispute would seem easily resolved with documentation, though Canadian prison and school records from that era were sometimes imprecise, lawyers in the case have said.

A key witness for Doig was a Canadian woman who told the court the painting is actually by her now-deceased brother, whose name was Peter Doige, with an "e", like the signature on the disputed work.

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Meanwhile, Mr Fletcher's lawyers suggest Doig is denying the painting is his work because, if Mr Fletcher is right, it would link him to prison in his youth.