Italy’s highest court on Thursday confirmed a slander conviction against U.S. defendant Amanda Knox for accusing an innocent man of murdering her British flatmate 17 years ago in a sensational case that polarized trial watchers on both sides of the Atlantic.

An American who was convicted and later acquitted of the 2007 murder of her British housemate, Ms. Knox was found guilty of falsely accusing someone else of the crime.

Italy's highest court on Thursday upheld the conviction of American Amanda Knox for slander in a case related to the murder of her British flatmate in 2007, the final act in a legal drama lasting almost two decades.