An EWN investigation has revealed dramatic information surrounding Oscar Pistorius.

JOHANNESBURG - Eyewitness News can today reveal dramatic information surrounding the Oscar Pistorius murder case.

EWN has learned that Pistorius's brother Carl narrowly escaped prosecution after police discovered he'd allegedly tampered with the athlete's phone in the days after Reeva Steenkamp was shot.

It's understood investigators considered charging him with defeating the ends of justice but ultimately declined to proceed with a case against him.

This revelation is contained in Behind the Door, a new book about the trial, authored by EWN senior reporters Barry Bateman and Mandy Wiener.

Pistorius was convicted of culpable homicide for the Valentine's Day shooting and will be sentenced on 13 October.

A study of the data extracted from Pistorius's personal phone shows the entire call history and every WhatsApp message had been deleted, as well as several messages sent to the device after the shooting.

This phone was only handed to the police a full 12 days after Steenkamp was killed.

In an attempt to track the whereabouts of the handset during that period, police investigators compared the service provider data of both Oscar and Carl's phones during that time.

This is how they established that it was likely the athlete's brother had removed the device from the crime scene.

After months of trying to access the handset, investigators established that it had been synchronised with a computer identified as Titanium Hulk.

Carl uses this comic book character name in his email address and often refers to himself as the Hulk on social media.

The National Prosecuting Authority declined to comment on this matter.

In a statement issued on Wednesday night, the Pistorius family says they are not aware of any deletions on the athlete's phone that could have affected the trial.

PISTORIUS SPOKE TO EX ON EVE OF SHOOTING

The EWN investigation has further revealed that Pistorius was talking to his ex-girlfriend minutes before he arrived home to Steenkamp on the eve of the Valentine's Day shooting.

The athlete had a nine-minute long conversation with Jenna Edkins, whose number had been saved under the name 'Babyshoes', just hours before he killed the model at his luxury Pretoria East home.

But the police did not uncover this piece of evidence.

While EWN understands that cellphone expert Captain Francois Moller provided his colleagues with a list of numbers from Pistorius's call records, investigators did not make a connection between Edkins's father's name (under which the phone was registered) and the athlete.

What impact, if any, would it have made to the state's case if police had joined the dots?

A member of the prosecution team says it would be wrong to suggest that the state missed a crucial piece of evidence.

The phone call would have been considered character evidence which it was not allowed to be led in court.

Prosecutors also would likely have had difficulty convincing Judge Thokozile Masipa about the contents of the phone call and its value.

A source close to the defence legal team is at pains to explain that this is not the great revelation the public has been searching for.

The 'Blade Runner's' lawyers knew about the phone call to Edkins all along and had consulted with her.

It's believed she was prepared to testify for the defence if the state attempted to introduce the phone call as a smoking gun.

The source insists the relationship was no longer romantic and Pistorius and Edkins are merely friends.

In response to questions from EWN , Edkins says its common knowledge she and her ex-boyfriend have remained friends over the years.