Darryn Walker had written a 12-page sexual fantasy about the rape and murder of the five members of reality television group Girls Aloud. The blog post was noticed by the Internet Watch Foundation, the non-governmental body which tracks images of child abuse, which reported it to the police.
Walker was arrested last year and charged, but prosecutors effectively dropped the case in a Newcastle court, offering no evidence against Walker.
Prosecutors said that this was because of evidence from a technology expert called as a defence witness who had provided a report claiming that young fans were unlikely to come across the blog post while looking for non-explicit material.
Prosecutor David Perry told the court that the case had been brought because young fans could stumble on the explicit material.
"A crucial aspect of the reasoning that led to the instigation of these proceedings was the article in question, which was posted on the internet, was accessible to people who were particularly vulnerable, young people who were interested in a particular pop music group," he said, according to local paper the Sunderland Echo. "It was that which distinguished this case from other material available on the internet."
Prosecutors received the defence's evidence earlier this month, though, and decide to drop the case because the evidence said that it was unlikely that the material would turn up in everyday searches for Girls Aloud material.
"[The expert's] evidence was in fact the article would not have been easily accessible to a person searching the internet and would only have been found by a person determined to find the sort of material contained within," said Perry. "It is not possible to rebut the information contained in the report and in the absence of information to contradict that evidence the CPS decided, again with counsel's advice, it was inappropriate to proceed with this case."
The prosecution was brought under the Obscene Publications Act. It was unusual because it related only to writing. Most modern obscenity cases relate to video and images after a 1976 case against a story called Inside Linda Lovelace failed. Police reportedly decided to stop prosecuting over written material after that case.
Free speech campaign group Index On Censorship said that the case threatened the rights of writers and internet users.
“This prosecution should never have been brought in the first place,” said Jo Glanville, editor of Index on Censorship. “Since the landmark obscenity cases of the 60s and 70s, writers have been protected from such prosecutions and have remained free to explore the extremes of human behaviour."
"This case posed a serious threat to that freedom. In future, obscenity cases should be referred directly to the director of public prosecutions before any prosecution is triggered," she said.
The court heard that Walker had lost his job as a result of the case. His lawyer said that "he had written what he describes as an adult celebrity parody, only meant to be read by like minded people [and] it had never been his intention to frighten or intimidate the members of Girls Aloud".