Kenyan free-speech advocates and lawyers have condemned the prosecution of the author of an unauthorised biography of Kenyan President William Ruto's daughter.

Charlene Ruto accused Webster Ochora Elijah of "misusing" her name by writing the book without first seeking permission from her.

On Tuesday, the author was arrested and charged with impersonation over the book titled Beyond the Name: Charlene Ruto and the Youth Uprising. He pleaded not guilty and was released on bail.

Ms Ruto told journalists that she had reported the matter to the police and was following legal procedures. She is listed as the complainant on the charge sheet.

The charge alleges that the accused published the book on or before 22 May, alongside others who are yet to be charged, with intention to defraud.

The president's daughter has not complained about the contents of the book, just that it was written without her permission.

But critics say this is not illegal.

Politician and lawyer Willis Otieno said to "criminalise authorship" was misusing the "state machinery in defence of fragile egos".

Literary critic Mbugua Ngunjiri said the author did "nothing wrong", giving an example of an unauthorised biography of former President Uhuru Kenyatta, in 2014, where the "author did not need to consult".

"A million writers can write 'her book' and it will be perfectly legal. The only time Charlene would be justified to go after the author is if he misrepresented her in any way," he posted on Facebook.

The president's daughter told journalists that there was a "bad culture" in Kenya "where we misuse people's names and we get away with it and that is not right".

She said the author had not sought permission from her and it did not matter whether the book was "positive" about her.

"The gentleman never came to me with a suggestion that he wants to write a book on my behalf and for me that is a misappropriate use of my name," she said.

The self-published book, by a little-known author, aged 25, has not been widely distributed and there is not much publicly available information about its contents. It is not available online.

His legal team have argued that his work did not constitute a crime. Lawyer Kennedy Mong'are told local media that he had previously written books about public figures, including on veteran politician Raila Odinga and US President Donald Trump.

Another lawyer, Evan Ondieki, said that high-ranking government figures should expect public scrutiny and that the arrest undermined Kenya's democratic values.

"You cannot be so thick-skinned that the use of your name or image becomes an offence," he stated.

In April, a secondary school teacher was charged for impersonating another daughter of President Ruto, by pretending to be June Ruto on Facebook.

Charlene Ruto is a high-profile figure who has in the past been likened to a version of Ivanka Trump, daughter of the US president.

She has often been a guest at public events, and in the past met leaders across the country and attended international forums.

In 2022, she denied that public money was being used to fund what she called the "Office of the First Daughter".

The court case has amplified concerns about restrictions on free expression, particularly following the recent detention of software developer Rose Njeri.

Njeri was arrested on Friday for creating a tool that helped citizens oppose the government's annual finance bill.

She was charged with cyber-crime and computer misuse on Tuesday and freed on bail until 20 June when the court will determine whether she will answer the charges.

She has since thanked Kenyans for raising their voices against her "ludicrous" arrest and detention.