Handset makers, the criminal's friend
See no evil, speak no evil
Don't care to share
Network operators probably wouldn't share if they weren't legally obliged to, and compensated for their costs. But while a network operator will be subject to national laws, a handset manufacturer will likely be located outside such a jurisdiction.
International agreements cover national security issues, and you can be sure that the more secret services have tools at their disposal. But that's no use to a cop trying to work out the identity of the corpse he is putting into the body bag.
The manufacturers don't want to share security models, or codes, for fear that once shared they're unlikely to stay secret for long. Miscreants getting hold of such codes might be bad publicity, for starters. But manufacturers are even more worried about what their competitors will think.
There are no standards for device security. One handset might yield to simple command, while another will stay secure against any attack: legally authorized or otherwise. The industry is very reticent to talk about specific models, but we understand that the police Phone Examination Units particularly dread receiving handsets from Sony Ericsson.
A few years ago the Metropolitan Police tried to set up a working group with the manufacturers, to define some common-access standards that would allow legitimate law enforcement access to mobile-phone handsets. With no motivation and no legal threats to make against them, the manufacturers saw no advantage in taking part and the project was stalled.
SIMs remain secure, within a legal framework that allows law enforcement to break that security. But until the same thing can be applied to mobile phones, the manufacturers will create more secure systems. The UK taxpayer, meanwhile, will continue to fund police forces and private companies in order to break that security, to the enormous frustration of everyone involved.®