"It's easy, you've got to have money and who you know," said Lionel Simmons, a Former Northern State inmate.
Information Eyewitness News obtained through the "Open Records Act", shows that in the last 4 years, 620 cell phones had been confiscated at Northern State.
That's more than double the number (295) found in New Jersey's 12 other prisons combined.
A former Northern State inmate says they're easy to get on the inside, but not cheap.
"$1,500, $1,000, $1,550, it all depends," Simmons said.
The cost all depends on whether you want just a regular cell phone or a smart phone which gives the inmate access to the internet, to its maps, directories and search engines, and to email.
"It makes the very concept of the prison obsolete. It allows the person in custody to transcend the walls of the prison," said Martin Horn, the Former New York City Correction Commissioner.
Former New York City Correction Commissioner Martin Horn says smart phones are the biggest problem facing prisons today.
"We send people to prison as punishment to separate them from society. We send them to prison to incapacitate them so they can no longer commit their crimes. Possession of a cell phone really makes those efforts futile," Horn said.
There's no better example of the dangers of cell phones in prison than the case of Anthony Kidd.
He's been charged with using a cell phone from inside a New Jersey prison to order his girlfriend's killing after she implicated him in a crime.
Ever since, the state has tried to crackdown on the problem, even using cell phone sniffing K-9 units.
Several sting operations suggest that prison staff members are bringing in the phones, something this former New Jersey inmate declined to confirm.
"You yourself were able to get a cell phone in prison?" Eyewitness News Investigator Jim Hoffer asked.
"Yeah," the former inmate replied.
"How did you get it?" Hoffer asked.
"I don't answer that question," the former inmate said.
New Jersey Department of Correction declined to do an interview for Eyewitness News' report.
Despite aggressive efforts to crackdown on cells phones, prison officials seem to be losing the battle as the number of smuggled phones keeps rising.
Several former inmates told Eyewitness News, more than half of the prisoners where they were locked up had phones.
"Cell phones in prison, how common?" Hoffer asked.
"Very common!" the former inmate replied.
"Easy to get?" Hoffer asked.
"Easy to get, yeah," the former inmate said.
"Why so easy?" Hoffer asked.
"The only difference between jail and street is women. Everything on the street you find in jail, everything in jail you find in the street," the former inmate said.
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