Does turning off a cell phone prevent the ability of cops to sniff the information out of it?

The research I’ve done on this subject indicates your phone must be turned on in order for the police to extract any of your info. However…I’m not sure if they have sophisticated equipment and software that will allow them to get around this issue.

If you mean your location, no. You have to remove the battery or put it inside a Gaussian shield to prevent that. Some phones, no doubt, can be hacked so that the entire contents of your phone are available.

If the phone is not powered up, then the radio is not broadcasting, and you cannot be tracked.

If course, if you turn it off, you can’t use it, so it’s sort of question of balance.

I don’t see how they’d get the location or any other info from the phone if it’s off.
Why would you need the extra step of removing the battery or putting it in a can ?

Also if it’s off there’d be no way to know you have one. So if they ask for it just say you don’t have one. If they search you and your car however who knows what happens then.

“Even if a cell phone is completely turned off, law enforcement authorities can still listen in on the conversations that a suspect is having. All that is necessary is for the battery to still be in the cell phone.

According to CNET News, the FBI can remotely activate the microphone on your cell phone and listen to whatever you are saying….

The FBI appears to have begun using a novel form of electronic surveillance in criminal investigations: remotely activating a mobile phone’s microphone and using it to eavesdrop on nearby conversations.

The technique is called a “roving bug,” and was approved by top U.S. Department of Justice officials for use against members of a New York organized crime family who were wary of conventional surveillance techniques such as tailing a suspect or wiretapping him.

When you make a telephone call, it is never private.” Source

Sounds like there is more to it: http://www.schneier.com/blog/archives/2006/12/remotely_eavesd_1.html

When your battery is plugged in, it’s constantly looking for usable towers. It sends its unique identifier string to those towers. From there, your position can be triangulated remarkably well.

@ro_in_motion define, ‘remarkably well’ and can you explain why you think that.

@cazzie The original iphone did it’s “gps” tracking by doing just that. It’s not as accurate but if you can be navigated using that, it’s ‘remarkably well’. :)

@ro_in_motion GPS is not the cell phone tower triangulation and it is not enough for a ‘turn by turn’ navigation.

@cazzie

I didn’t say it was. They are two different techniques. Again, in the original iPhone, triangulation was used.

@ro_in_motion I guess we have different definitions of ‘can be navigated’ then. GPS finds your location to cm. Triangulation is lucky if it finds where you are in a 3–4 city block radius.

“When your battery is plugged in, it’s constantly looking for usable towers.”
It does this even if the phone is turned off ?? No way.

The restriction of cell phone use on flights, for example is not mandated by the FAA, it’s mandated by the FCC because a cell phone that’s on will contact all the cell towers along the way making a huge amount of chatter in the system as cells get your phone and pass it to the next cell right away.
If cell phone still contact the cell towers when they are off then it would not help to turn them off on planes.

Triangulation is good enough that there are plenty of apps that use it to locate a cellphone that is lost or stolen. I’m not sure how accurate that is, but it is a hell of a lot more accurate than three or four blocks. Check out Where’smyAndroid. It can use triangulation when GPS is off in order to find the phone.