South Africa's Director of Public Prosecutions has accused a Bristol man of ordering his new wife's murder and of committing a "heinous crime".
South African authorities want Shrien Dewani to return to stand trial for the alleged contract killing of wife, Anni.
Mr Dewani's spokesman, Max Clifford, said it was "absolutely frightening" that prosecutor Menzi Semelani appeared to have pre-judged the case.
Mr Dewani is currently on bail in the UK, but may face extradition.
'Pure criminal matter'
Mr Semelani made the comments during an interview on South African television about the extradition process.
He told SABC3: "This is a pure criminal matter of somebody who murdered his wife whilst he should be celebrating his honeymoon.
"The facts here are that the accused that is sought to be extradited came to the country and committed what is a very heinous crime."
Shrien Dewani, 31, and new wife, Anni, 28, a Swedish national, were on honeymoon in South Africa and had been married for two weeks.
The couple's taxi was hijacked on 13 November in Cape Town as they travelled through the Gugulethu township.
Mrs Dewani's body was later found in the abandoned car. Mr Dewani had been released unharmed.
Max Clifford said: "This is absolutely frightening. The fact that the national prosecutor has already found him guilty and described him as somebody who has committed a heinous crime, you can see why we are very worried about what awaits him if he goes back to South Africa."
A spokesman for the Dewani family said: "The family will not enter into criticism or debate regarding the South African Prosecution Service or authorities but will raise all issues in the legal proceedings where Shrien will be cleared of all the false allegations against him."
Lawyers for Mr Dewani, who is said to be suffering from severe post-traumatic stress disorder and clinical depression, will argue that he will not receive a fair trial if he is extradited.
Shrien Dewani is due to appear before City of Westminster Magistrates Court on 23 March for the next stage of the proceedings, with a three-day extradition hearing set for 3-5 May.