Three words: Get a Warrent

It's an invasion of our privacy; nothing in the constitution gives this power, so it does not exist. It's an over-stretch by "the authorities" to even ask. Not to mention it's unreasonable to require the carriers to bear the cost to facilitate this (which in the end means the cost will be past on the the consumers). So in the end I'd end up paying for an invasion to my privacy... two words: No Way!