Amanda Knox was again found guilty of slander Wednesday in a retrial in Italy linked to her infamous jailing and later acquittal for the 2007 murder of her British roommate.

The American cried in court in Florence as she was sentenced to three years already served for having accused, during police questioning, an innocent bar owner of killing 21-year-old Meredith Kercher.

"Amanda is very upset at the outcome of this hearing, she was looking to have a final point after 17 years of judicial procedure," her lawyer Carlo Dalla Vedova told journalists outside court.

He added: "We are very surprised at the outcome, the decision. We need to read carefully the motivation which will be available in the next 60 days. "

After that, they would decide "next steps" and may appeal.

Knox was 20 when she and her Italian then-boyfriend were arrested for the brutal killing of student Kercher at the girls' shared home in Perugia.

The murder began a long legal saga where the pair was found guilty, acquitted, found guilty again and finally cleared of all charges in 2015.

But Knox still had a related conviction for slander.

During police questioning, Knox implicated Congolese bar owner Patrick Lumumba, who then spent almost two weeks behind bars before being released without charge.

Knox was convicted of slandering him in 2011 and sentenced to three years already served.

But she said she was yelled at and slapped during the police investigation.

The European Court of Human Rights in 2019 ruled that Knox had not been provided with adequate legal representation or a professional interpreter during her interrogation.

In October, Italy's highest court threw out the slander conviction on appeal and ordered a retrial.

Knox, now 36 and married with two young children, returned to Florence to defend herself in court on Wednesday.

She blamed police for forcing her into the statement, saying she was "scared, tricked and mistreated".

"I'm very sorry I was not strong enough to have resisted the police pressure," Knox told the judges.