Dr John Donaldson was called as a Crown witness in the High Court at Auckland this afternoon where he described the movements of the defendant before and after he allegedly killed the mother of three.
The 28-year-old man has been on trial in the High Court at Auckland since last week accused of Mrs Gotingco's rape and murder.
He has name suppression, though his image is allowed to be published.
The Crown says just before 8pm on May 24 last year, the defendant deliberately ran her down in his car as she walked home along Salisbury Rd from work.
It is alleged he then bundled her into his silver BMW and took her back to his nearby apartment complex in Birkdale where he raped her, slit her throat and stabbed her to death.
On May 26, police with search and rescue found the body buried under scrub in Eskdale Cemetery.
The defendant was on an 8pm to 6am curfew -- monitored by Corrections via a GPS anklet -- at the time and Dr Donaldson reviewed that data.
Just before 6pm, GPS co-ordinates put the murder accused around the Eskdale Cemetery for about 15 minutes, before he allegedly drove up and down Salisbury Rd.
He returned home for more than an hour before again driving down the street in Birkdale -- the device putting him there at the time Mrs Gotingco was allegedly struck.
The defendant returned home just before his curfew but Dr Donaldson said he was back at the cemetery at 6.18am the following morning for 20 minutes.
By 6.44am he was back in his apartment.
Amicus curiae of the court Chris Wilkinson-Smith questioned the reliability of the GPS data, which at times had a margin of error of up to 100m.
Dr Donaldson said he was not in court to vouch for the accuracy of the data supplied to him, only to plot it on a map.
After a dawn raid on the man's house on May 27, police took him to the station and charged him with murder.
A search of the property allegedly turned up a knife with traces of Mrs Gotingco's blood on it, as well bloody towels and mops.
The Crown said some of the victim's items were found buried in the backyard.
By Rob Kidd, NZME. News Service court reporter
