The ACLU have issued a report stating that the US government are circumventing the checks and balances on surveillance operations by increasingly using private corporations to gather the information for them. Private companies are not subject to the same restrictions on the gathering of personal information and people trust them more than they trust the government, so are more willing to unquestioningly hand over personal details.

"The Privatization of Surveillance
The U.S. security establishment is rapidly increasing its ability to monitor average Americans by hiring or compelling private-sector corporations to provide billions of customer records. The explosive growth in surveillance by government and business is creating a "Surveillance Industrial Complex" that threatens all of our privacy."

Wired have an article covering the report.