# Jamming cell phone signals in public venues **URL:** \ **Category:** Factual Questions\ **Created:** [December 30, 2005, 3:53am UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679 "2005-12-30T03:53:41Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![RedDawgEsq](https://avatars.discourse-cdn.com/v4/letter/r/dbc845/32.png) [@RedDawgEsq](https://boards.straightdope.com/u/RedDawgEsq)\ **Post date:** [December 30, 2005, 3:53am UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/1 "2005-12-30T03:53:41Z")
Many are the intrusions of cell phones ringing inappropriately in public venues such as theatres, churches, concerts, etc., by the thoughtless or careless owners who will not/do not turn them off or switch them to a silent signaling mode such as vibration. Cell phone jammers (transmitters that emit intentionally interferring signals in the cell phone frequency spectrum) are getting a lot of press these days, primarily because they are (currently) illegal (in the USA at least) and may subject the user to legal difficulties if, through their use, a cell phone user (such as a doctor) could prove that they prevented a bona fide emergency from reaching him/her. Although a lot of things would have to happen to allow the following, is there any fundamental reason why this scenario would not work, at least for incoming calls? Virtually all cell phones manufactured today have a silent ring mode, normally a vibration element. Also, all phones (I think) already have GPS locating capability which is usually user-selectable to activate either for all calls or emergency (911) calls only. I don’t know how this feature was mandated, but I’ll guess the FCC had something to do with it. Now, suppose the FCC (or whomever has the clout with phone manufacturers), would require all cell phones sold in the US to have a feature whereby the phone could be remotely and automatically switched into silent ring mode according to this scheme: The resolution of the GPS system that is available to the public for navigation purposes is about 1 meter I believe. Theaters and similar venues could define the “footprint” of their facilities in terms of GPS coordinates. After applying to the FCC, being vetted according to some “worthiness” criteria, and presumably paying a fee for the privilege, their GPS footprint would be entered into a cell phone “exclusion zone” data base. Cell phones (which already check their positions with respect to the closest cell tower periodically) would be programmed to periodically and automatically check their GPS locations and query the data base. Any phone that has moved inside an authorized exclusion zone would be commanded automatically to switch to a silent ring mode and remain in that mode until a subsequent periodic location check showed that it was no longer in the exclusion zone. Obviously there would be a change-over period while non-compliant phones rotated out of use, but if the concept was adopted and implemented soon, a workable system could probably be in place within 2-3 years. The biggest problem I see is getting all cell phone manufacturers to incorporate this feature, although it should be a relatively simple programming change. This should be legal since you are not blocking incoming signals, simply commanding the phone remotely into silent ring mode. Outgoing calls would not be affected, but that is a different problem anyway. And there are probably some privacy concerns, but they should be soluble. FCC, are you listening? ---
**Author:** ![CynicalGabe](https://avatars.discourse-cdn.com/v4/letter/c/3e96dc/32.png) [@CynicalGabe](https://boards.straightdope.com/u/CynicalGabe)\ **Post date:** [December 30, 2005, 4:25am UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/2 "2005-12-30T04:25:11Z")
> [@](#): > > may subject the user to legal difficulties if, through their use, a cell phone user (such as a doctor) could prove that they prevented a bona fide emergency from reaching him/her. Using the jammer is in and of itself, illegal, regardless of whether it inconveniences someone. That would simply open up additional civil or criminal liabilities. > [@](#): > > Although a lot of things would have to happen to allow the following, is there any fundamental reason why this scenario would not work, at least for incoming calls? Issuing remote commands to someone else’s phone would likely be much more illegal than operating a jammer. For the same reasons as hacking someone’s computer without permission, regardless of your reason for doing it. Is that your only question? Most of your post seems more suited for GD. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [December 30, 2005, 5:29am UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/3 "2005-12-30T05:29:21Z")
> [@RedDawgEsq](#): > > is there any fundamental reason why this scenario would not work A very similar thing was suggested in this thread [http://boards.straightdope.com/sdmb/showthread.php?t=270056](http://boards.straightdope.com/sdmb/showthread.php?t=270056) about a year and a half ago. But that involved the venues setting up a small local transmitter that sent out a signal to cell phones to switch to vibrate mode. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [December 30, 2005, 2:22pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/4 "2005-12-30T14:22:05Z")
Like anything else freedom requires responsibility, if you are not responsible with your freedom it will be taken away (though this is being taken away ‘by the people’ instead of ‘big brother’). You can see this pattern in smoking, leash laws, and lots of driving laws. Once your freedom starts seriously interfering with others in a society the freedom has been abused and on the short list to go IMHO. Perhaps a tech solution can emerge where phones would automatically switch to vibrate or silent when in certain areas (as pointed out above), if not I suspect we are going to see more of these jammers. ---
**Author:** ![RandomLetters](https://avatars.discourse-cdn.com/v4/letter/r/8edcca/32.png) [@RandomLetters](https://boards.straightdope.com/u/RandomLetters)\ **Post date:** [December 30, 2005, 4:47pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/5 "2005-12-30T16:47:42Z")
Now, are they any laws that say you can’t passively block cell phones within an area - i.e. when you build the building, have a metal mesh of the right spacing to block the radio waves used by cell phones included into the walls? ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [December 30, 2005, 5:12pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/6 "2005-12-30T17:12:45Z")
> [@CynicalGabe](#): > > SNIP > > Issuing remote commands to someone else’s phone would likely be much more illegal than operating a jammer. For the same reasons as hacking someone’s computer without permission, regardless of your reason for doing it. > > SNIP I think he actually has a grand idea there, and one that could be implemented, with some planning, by cell phone companies and manufacturers with some regulatory help. I would suggest making the “silent mode command” something sent by the network and obedience to the command a configurable option in the phone settings. I would guess that 98% of vibration-capable phones ringing in inappropriate venues are accidentally left in audible states by their users. Implementing this feature would be in the interest of cell phone providers, and it would be quite easy to render it wholly lawful by simply inserting an agreement to this system into the consumers’ terms of service with the CellCo. And yeah, the technical question is GQ, but discussions of “should we” probably belong in GD. ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [December 30, 2005, 5:14pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/7 "2005-12-30T17:14:12Z")
> [@RandomLetters](#): > > Now, are they any laws that say you can’t passively block cell phones within an area - i.e. when you build the building, have a metal mesh of the right spacing to block the radio waves used by cell phones included into the walls? The Wal-Mart next to my job sure as heck seems to get away with the functional equivalent. I have 5 bars in their parking lot, and inside I have 0-1 bars with the phone ringing about half the time I receive calls. ---
**Author:** ![Raguleader](https://avatars.discourse-cdn.com/v4/letter/r/258eb7/32.png) [@Raguleader](https://boards.straightdope.com/u/Raguleader)\ **Post date:** [December 30, 2005, 9:01pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/8 "2005-12-30T21:01:43Z")
> [@Mr. Slant](#): > > The Wal-Mart next to my job sure as heck seems to get away with the functional equivalent. > I have 5 bars in their parking lot, and inside I have 0-1 bars with the phone ringing about half the time I receive calls. The PX at Fort Huachuca gets excellent cell phone reception… except in the Electronics Section, which is strangely a cell phone black hole. 😛 ---
**Author:** ![Cluricaun](https://avatars.discourse-cdn.com/v4/letter/c/bb73d2/32.png) [@Cluricaun](https://boards.straightdope.com/u/Cluricaun)\ **Post date:** [December 30, 2005, 9:41pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/9 "2005-12-30T21:41:37Z")
Is a remote signal even capable of giving a current design cell phone such a command, to switch from ring to vibrate? If feasible, couldn’t the same technology be used to, say, cause everyone’s cell phone to call into American Idol and vote for a particular participant? ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [December 30, 2005, 9:52pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/10 "2005-12-30T21:52:47Z")
Blocking cell reception outright could easily cost lives if it prevented an on-call physician from getting a call to report to the hospital and save someone’s life. Because one person’s life is worth more than a million people’s irritation, I hope it is (and remains) illegal to knowingly block cell phone signals. A signal to switch phones from ring to vibrate sounds like a captial idea, but there are still cell phones that don’t have a vibrate mode (mine is one of them) and cell phones that do but simply don’t comply with the relevant standard. Such is life. ---
**Author:** ![RogueRacer](https://avatars.discourse-cdn.com/v4/letter/r/7ab992/32.png) [@RogueRacer](https://boards.straightdope.com/u/RogueRacer)\ **Post date:** [December 30, 2005, 10:19pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/11 "2005-12-30T22:19:20Z")
> [@Derleth](#): > > Blocking cell reception outright could easily cost lives if it prevented an on-call physician from getting a call to report to the hospital and save someone’s life. Because one person’s life is worth more than a million people’s irritation, I hope it is (and remains) illegal to knowingly block cell phone signals. This gets brought up every time the whole cell phone/theater issue is mentioned. If the physician is on call, maybe he/she shouldn’t be at a theater? Just a thought. Sorry, nothing to add to the OP. ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [December 30, 2005, 10:25pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/12 "2005-12-30T22:25:30Z")
> [@RandomLetters](#): > > Now, are they any laws that say you can’t passively block cell phones within an area - i.e. when you build the building, have a metal mesh of the right spacing to block the radio waves used by cell phones included into the walls? No. The FCC has no authority over things that broadcast nothing. If you build a grounded steel building, like my favorite supermarket, in which cell phones do not work, there is no crime. If I were building a theater or restaurant, I’d line the walls with grounded wire screen. Another lovely solution is one I’ve read about. A big sign at the door of some pubs says, “Turn off your cell phone now. If if rings while you are in here, you must buy a round for everyone in the joint.” It is strictly enforced, to the delight of those who comply. 🆒 ---
**Author:** ![spingears](https://avatars.discourse-cdn.com/v4/letter/s/ebca7d/32.png) [@spingears](https://boards.straightdope.com/u/spingears)\ **Post date:** [December 30, 2005, 11:16pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/13 "2005-12-30T23:16:12Z")
> [@RedDawgEsq](#): > > Many are the intrusions of cell phones ringing inappropriately in public venues such as theatres, churches, concerts, etc., The local county courts have a VERY effective way to discourage cell phone ring tones disturbing the court proceedings. Any cell phone which rings is immediately confiscated permanently by the balifs and it will NOT be returned under any circumstances. Tuff stuff! ---
**Author:** ![Corrvin](https://avatars.discourse-cdn.com/v4/letter/c/bbce88/32.png) [@Corrvin](https://boards.straightdope.com/u/Corrvin)\ **Post date:** [December 31, 2005, 9:05am UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/14 "2005-12-31T09:05:55Z")
> [@RogueRacer](#): > > This gets brought up every time the whole cell phone/theater issue is mentioned. If the physician is on call, maybe he/she shouldn’t be at a theater? Just a thought. Sorry, nothing to add to the OP. You may not be aware of this, but some doctors are **always on call**. Either they don’t share a practice with anyone, or they simply prefer being available for their patients (or no one else has their same specialty). One doctor I know well had been on call continuously since his partner left the practice eight months ago, until a new doctor with the same specialty joined him. It’s also common practice that unless a doctor is out of town or otherwise indisposed, they are the back-up in case the on-call doctor cannot be reached (which would happen if the on-call doctor was in a car wreck, or had a family member seriously injured.) Basically, a doctor is almost always on-call, even if they’re not the top of the list. Do you think doctors ought not to EVER go to theaters? ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [December 31, 2005, 11:46am UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/15 "2005-12-31T11:46:16Z")
> [@RogueRacer](#): > > This gets brought up every time the whole cell phone/theater issue is mentioned. If the physician is on call, maybe he/she shouldn’t be at a theater? Just a thought. Sorry, nothing to add to the OP. So why should a person who saves lives be unable to have one 3-4 days a week? Your argument, however, is beyond saving. Call it. ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [December 31, 2005, 11:50am UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/16 "2005-12-31T11:50:44Z")
> [@spingears](#): > > The local county courts have a VERY effective way to discourage cell phone ring tones disturbing the court proceedings. > Any cell phone which rings is immediately confiscated permanently by the balifs and it will NOT be returned under any circumstances. I hope they make reasonable allowances for physicans and nurses who are on call, but the odds of an on-call _anyone_ having to attend a court proceeding seem slim to none. And I’m glad consideration is being shown for the poor court stenographers. Taking down dictation is hard enough without alarms ringing. ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [December 31, 2005, 2:51pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/17 "2005-12-31T14:51:21Z")
> [@Derleth](#): > > I hope they make reasonable allowances for physicans and nurses who are on call, but the odds of an on-call _anyone_ having to attend a court proceeding seem slim to none. > SNIP If you have duty in court, you are unavailable to perform your professional non-court responsibilities. If unable to get out of going to court you will need to inform your employer that they have to retain a substitute for you. We can hardly have witnesses up and leaving the courtroom mid-trial. Same goes for defendants. Even if the judge goes for it, that kind of thing would wreck the schedule of everyone else who has to appear in court. I suppose that alternate jurors might be a workable solution, but in a lengthy trial you’d be more or less _guaranteed_ that Surgeon Smith would wind up getting excused to go do his Marcus Welby impression at County City General Local Private Medical Center. It sucks, but if an on-call professional needs to appear in court for any reason except for jury duty, you’ll need to find them a substitute at work. Jury duty, I can imagine you could weasel out of. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [December 31, 2005, 4:27pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/18 "2005-12-31T16:27:29Z")
For people who need to be on call, I suggest getting permission from the owner/manager. The owner can set the policy as he sees fit: allow it, have the Dr check the phone and he will be alerted if it goes off, or disallow it and have the Dr take a hike. ---
**Author:** ![Raguleader](https://avatars.discourse-cdn.com/v4/letter/r/258eb7/32.png) [@Raguleader](https://boards.straightdope.com/u/Raguleader)\ **Post date:** [January 1, 2006, 7:09pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/19 "2006-01-01T19:09:12Z")
> [@Corrvin](#): > > Basically, a doctor is almost always on-call, even if they’re not the top of the list. Do you think doctors ought not to EVER go to theaters? EXACTLY! He shouldn’t be watching MOVIES or going on DATES! He should be STUDYING MEDICAL BOOKS so he will be better equipped to save my life if I need it! 😃 I suppose I can make an exception if he’s watching a movie about doctors, like Doc Hollywood, or maybe if he’s at a buddy’s place watching Scrubs. 🙂 ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [January 1, 2006, 7:39pm UTC](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679/20 "2006-01-01T19:39:31Z")
> [@kanicbird](#): > > For people who need to be on call, I suggest getting permission from the owner/manager. The owner can set the policy as he sees fit: allow it, have the Dr check the phone and he will be alerted if it goes off, or disallow it and have the Dr take a hike. No. This solution is not robust enough and, quite frankly, wouldn’t work very well even in ideal conditions. In less than ideal conditions, it could kill someone. (The sign announcing cell-blocking signals wasn’t posted precisely right, the doctor got a call while he was waiting for someone to talk with about the blocking, the 16-year-old twerp assigned to run calls out gets waylaid by an attractive female, etc. etc. etc. _ad nauseum_ Not a good solution.) [Next page](https://boards.straightdope.com/t/jamming-cell-phone-signals-in-public-venues/337679.md?page=2)