Taking apart an iPhone 4(S) is fairly straightforward and the various connectors on the boards inside appear to be pretty much "standard". The various flavors of 5 shouldn't be too far off. I would expect some levels of the law enforcement to even have the know-how and equipment to connect to those ports and access an iPhone's internals beyond the device's standard operation - and I don't think it's anything wrong with that. By the user experience it seems that the iPhone's memory is not scrambled.
Assuming anyone would use that, at least we can hope now that such an expensive phone will still be functional when the process is done.