SOLANO COUNTY-

Just as humans have built ways to keep prisoners away from the world, prisoners have devised ways to keep their secrets away from us.

At prisons across the state, inmates spend up to $500 for a cell phone and up to $2000 for smartphones, according to Paul Medina, Assistant Gang Investigator at CSP Solano. He says many times, they’re used for illegal activity.

“Hits are called from in here,” he said. Medina added that much of the gang leadership is in prisons. “Those assaults are – can be – orchestrated from here with those cell phones.”

Illegal communication started long before the cell phone era though. Prison gang leaders would give relocating prisoners thin slips of yellow paper with sensitive information –essentially background checks – on new prisoners. Medina said those slips were secreted in an inmates rectum. Sheets were found as recently as six months ago.

“These inmates have their own set of laws to function in here and certain gangs have strict guidelines to stay on the main line,” Medina told FOX40. “If that inmate is found to be on a bad news list, then he’ll get assaulted.”

Now, much of that information is conveyed through cell phones.

Sgt. Jeremy Packard said the K9’s they have find cell phones, heroin, cocaine, marijuana, virtually anything they need them to.

“Everything has a unique odor, and so do cell phones,” Packard said.

Just in the time FOX40 was there, Scout, the dog we followed, alerted officers that six of the 25 rooms needed to be searched. Eventually two cell phones were found, hidden in an oatmeal box and in a mattress.

A lot of effort is put into tracking down a few cell phones, but it helps keep the public safe.

“There’s been times when a cell phone is ringing and it’s on my desk, so I’ve answered it, identified myself, and the individual on the other end of the line is shocked they’re talking to a corrections officer and they’re stunned when I tell them the call was originated by an inmate that we have in prison,” Medina said.

He says inmates will often develop relationships with people on the outside over periods of time through social media, and eventually ask for money or other items.

So how do the phones even get in the prison? Prison officials told us off-camera that they believe staff is often to blame. Some cell phones also come in through the mail – sometimes in cut-out legal paperwork or hidden in boxes. Sometimes phones are also thrown over prison fences by family or friends.

In the last month alone, about 40 cell phones were found at Solano Prison, and Medina says there are more out there.

He says they’re looking at ways to cut off illegal cell phone signals altogether.

“One thing they’re looking at right now is called managed access. It eliminates the cell phone signal from contraband cell phones and those cell phones that are allowed for prison personnel to have, they’ll allow that signal to go through,” Medina said.

To keep people on the inside and those of us on the outside safe, Medina says they always have to say one step ahead of the inmates.

“We just come up with new ways to search, to surprise them – and we do.”