The 17-year-old, known to friends as Barbie, was found dead at her jeweller boyfriend Elliot Turner's Bournemouth bungalow last weekend.
He and another male were arrested - then bailed - but have not yet been charged. A drug overdose is reportedly behind the aspiring model's death, which is being investigated by coroner Sheriff Payne.
Local and international media reported Longley was sent to the United Kingdom to live with her grandparents amid concerns she was mixing with the "wrong crowd" about two years ago.
Sources close to the girl said she had been a frequent user of ecstasy and been visiting nightclubs for the last two years.
And the Sunday Star-Times has learned the former Westlake Girls High School student appeared in court - twice in two months - before leaving New Zealand to live with her grandmother, Zosia. Legal reasons prevent details about the court appearances being published.
A close friend, who had known Longley for about five years, said after the court appearances her separated parents, Mark and Caroline, felt it would be best for their daughter to go overseas.
"Her parents wanted to send her away because she was going into town underage and getting pissed, have a pill or two and getting involved with the police and stupid situations," said the friend, who did not want to be named. "She was just another teenage girl going through the same stuff everyone else was."
The Star-Times also learned Longley's father was arrested for domestic assault in January 2009. He received diversion.
Despite the bid to get Longley away from drugs, her UK boyfriend Turner - a self-described "ladies man" who is pictured on Facebook and Bebo enjoying a champagne and limousine lifestyle - appears to be exactly the type of individual her parents wanted to get her away from, close friends said.
Turner's social network profiles are littered with commentary about late-night adventures, with reference to a need for "rehab" and being "under the influence". He lists his favourite sport as running from taxis without paying the fare. In 2008 he wrote on Bebo that he had to visit "the station" over an incident at his home.
The girl's father, newly appointed managing editor of the provincial Whakatane Beacon newspaper, is currently in England with his partner, photographer Hillary Upton.
He refused to discuss the tragedy or his domestic assault charge. "This is a highly distressing time and we ask you respect our privacy."
Close friends of the aspiring model said they were "too scared" to talk about their friend's New Zealand life after her father contacted them from England last week asking them not to give interviews. One friend who had already spoken to a reporter was reprimanded.
Meanwhile a cordon at Turner's home was removed on Saturday night although it is understood about 10 officers are continuing to work on the inquiry.
Detective Inspector Neil Devoto of the Major Crime Investigation Team told the Star-Times he still could not say exactly how Longley died and refused to say whether suicide was being considered. "It is up to the coroner to determine the cause of death," Devoto said. Toxicology test results could be two weeks away.
Another friend of Longley's said she had a theory on what happened: "I would say she has gone back to her same old ways, had a big night, someone has given her something and she has taken it and it's just reacted wrongly."
The public are still being asked to contact police if they had information.
"Officers are appealing for anyone with information about Emily's death or her actions before her death, or anyone who has witnessed anything suspicious."