Pass a local law making it illegal to use a mobile phone in a prison, thus there won't be any legitimate mobile traffic and the jamming law is nicely circumvented. (Hell, they're even using jammers in call centres over here to stop the operators slacking off...)

Paris 'cos well,

Stick a large speaker outside their rooms attached to an amplifier and coil of wire. Just listten out for the loudest one. Or hook it up to a PC / ADC / etc and find the highest induced current. Costs wouldn't be horrendous and no laws are broken.

Or give the guards mobile-phone-frequency-tuned unidirectional aerials and let them do a sweep every so often.

Could we put jamming technology in cinemas and theatre's?

I miss the days of being pissed off by the cretins rustling their sweet packets as they try to starve off starvation during a 90 performance. Nowdays, it's a case of "Yeah, I'm at the movies, innit!"

Or do you prefer "Mobile"?

Well in that case, you can bloody well type "mobile" when you're talking about telephones as well. It's not difficult and nobody calls them "mobes" anyway.

Grrr.

Surely a much better idea is to set up an in-prison base-station and tap all outgoing calls. It shouldn't be hard to get a warrant, there is near-certainty that they are all evidence of a crime, that of a mobile having been smuggled into the jail. Calls from outside could be distinguished and not intercepted using mobile-triangulation to see that the phone is not inside the walls. In the same way it might even be possible to pin-point which prison cell the call is coming from!

Use any evidence of more serious criminality against the criminals who are continuing to run gangs, drugs operations, etc. from inside. As for the lags who are just chatting to relatives, either let them carry on or just disconnect those hand-sets from the network.

Blanket jamming would work (but I wouldn't want to be the person that has to go through every nook and cranny of the prison making sure that there are no unjammed "livespots")

"Cleverer solutions" would probably be fairly quickly met with hacked, "cleverer" handsets that lock on to the second strongest source, thereby bypassing the local "goes nowehere" base station.

Paris, 'cos she has experience of mobiles and prison

What legitimate use would a prisoner have for a mobile?

Since they have already broken societys' rules and are in prison to be punished by a removal of freedom why would society have an interest in allowing them to have another form of freedom.

I am also confused as to why prisoners feel they have a right to anything anyway.

It wasn't too long ago that at least the more serious offenders would be permanently prevented from causing any harm whatsoever to anyone.

ttfn

PH 'cos you never can tell when technology might get misused.

Just make sure there aren't any live power sockets available to prisoners. The phones will run out of charge eventually - just make sure the inmates can't charge them.

To accelerate the process, paint the windows with mobile-unfriendly tint - and put up some corrugated iron cladding on the walls, to help sheild the place from signals as much as possible.

Install the base station and have all calls directed through the prison switchboard. Any legitimate call can still be made, but an inmate would have to be particularly inventive to scam a call through.

...books on how to learn Morse Code, or keeping carrier pigeons.

Sodding Hell, can't they fucking think?? Anyone capable of organising an escape is well clever enough to learn morse code - no torchlight, just a white or mirrored object 'flashed*' from the window.

Oh, better still, ban windows*.

*There's the IT angles.

Can't the calls just be jammed using a Faraday cage? Coat the prison in chicken wire and pretend it's for security.

Failing that, maybe put up a sign saying 'no mobiles'.

As far as I know prisoners are still covered by the first amendment. They should be a lot more worried about of drugs and weapons. Presumably if they can't keep phones out they're missing much more important things too.

I have "friend" who has a jammer which "he" uses on train when he doesn't want to listen to peoples inane whittering about their personal lives and it's great but also very illegal. Anyone who's been to a London cinema in the last month knows why they should be legalised.

Let the TSA do the searches - this would give them a little actual practice in finding things that are being smuggled in, rather than the usual 'security theater' that is the case in the airports.

Use signal triangulation to find out where exactly the mobiles are, and therefore which prison cells to search.

Check the operators for mobiles which are ALWAYS connected to masts in the vicinity - almost nobody but a prisoner will NEVER leave the area. Then go after those SIMMs - get the numbers and find out who they are calling / texting. Should give a pretty good idea of who has the phone.

In the last resort they could take a lesson from the Afghans - point guns aggressively at the mobile operators until they shut down the masts, perhaps even blow a few up...

Why Paris? - read the last few words again...

Set up a base station that all calls must go through from within the prison. Install a low-level jamming field so that the "second strongest" source isn't available. Require a PIN to be entered for a call to be connected. If the PIN is entered incorrectly, say 3 times, the station should no longer accept calls from that ESN (handset) Or allow them to connect but record the call automatically if a bogus PIN is entered.

"Pass a local law making it illegal to use a mobile phone in a prison"

OK, so i'm a lawyer visiting my client in prison and I can't call out....hello????

OK, so i'm a prison official in an emergency situation and I can't call out....hello???

@nigel - tap all outgoing calls... A clear violation of just about as many laws as you can count.

... is a giant aluminium foil deflector beanie, large enough to be lowered over the entire prison!

http://zapatopi.net/afdb

Problem solved!

Hell, SC has it easy. Last week a state senator here (in Tejas) said that he has received several calls from an inmate on death row, of all places. IIRC, the inmate in question is scheduled for a face-to-face with God next week, so he won't need his much longer.

Civil rights? Got none. If you've been convicted of a felony, you can not own a firearm (ever), get a passport, vote, touch your naughty bits in public (oops, never mind).

Phone calls from prison are a very sore point for COs. Many gangs continue to run effectively long after the leadership is sent away.