This is not going to be a popular opinion, but I think a compromise is necessary. There is no way to stand up to the train of data collection. For one, the public being afraid of this and that will demand to be protected at all costs, no matter how small the threat. The more scandalous the news cycle gets, the more panic we will see. And then the technology improves so fast, soon enough publicly installed video cameras will track everyone, and all within the constitutional framework.
A middle ground would be to create the fourth branch of the government that is tasked with data collection, but will only give it up on court order. Orders may be for individual incidents based on reasonable cause, or for data-mining, based on a judgement of proper scope.