Tracking tech called in

Court looks at mobile phones in Ristevski case

A NEW tool used by Optus that can pinpoint the exact location of a phone helped track the last activity of slain mum Karen Ristevski’s mobile phone, a court has heard.

Optus technician Oleg Prypoten, giving evidence in the Melbourne Magistrates’ Court yesterday, said the CovMo geolocation technology was able to detect phone activity despite Mrs Ristevski’s mobile being deactivated from the network on the day she went missing.

Usually, a phone could only be tracked when it was on.

He said Mrs Ristevski’s phone was cut off from the network at 11.40am, last pinging from a cell tower in the Gisborne region, on June 29, 2016.

Her husband Borce’s phone had been cut from the network at 11.09am, he told the court.

Mr Prypoten said the disconnection of both phones could be from three things: the phone was switched off, flight mode was activated or the battery died.

Mr Ristevski’s phone did not reconnect to the network until 12.51pm.

His wife’s phone never reconnected.

But Mr Prypoten said by using CovMo — recently bought by Optus to resolve network issues more quickly — they were able to detect a call was made to Mrs Ristevski’s phone at 1.19pm.

The network recorded a “voice call attempt” at this time to her phone, which they were able to trace to the SunburyDiggers Rest area, he said.

The evidence is being used by police, who allege Mr Ristevski, 54, drove from his Avondale Heights home, up the Calder Freeway, to Mt Macedon, where he dumped his wife’s body.

They have accused him of turning both his and his wife’s phones off along the way to avoid detection.

The phone record data had Mrs Ristevski’s mobile pinging from a cellular tower in the Maidstone area at 9.18am.

At 10.43am, the phone pinged from a Keilor East tower, before connecting to a Gisborne tower before it was cut at 11.40am.

Defence lawyer David Hal- lowes quizzed Mr Prypoten about which cell towers picked up both the Ristevskis’ phones and the distance the radio waves could travel.

Mr Prypoten said phones could ping up to 20km away from a tower in the Melbourne city region, while in rural areas it could be up to 35km.

Mr Ristevski, 54, denies any involvement in the disappearance of his wife of 27 years.

He told police she walked out of their home to clear her head after they fought over finances. The hearing continues.