The piece below was first published as part of the New York Times Room for Debate feature "Reining in the N.S.A.," which used this conversation starter:

Last week the House voted to limit the National Security Agency's sweeping collection of telephone records. But the bill approved was scaled back at the last minute and was sharply criticized by the technology sector, privacy advocates and others . Is the legislation heading now to the Senate strong enough to protect privacy? Or is there more that should be done to limit surveillance?

Ambiguities in the measure that passed the House last week would leave the door open to the same kind of abuse we've seen (but only recently learned about) in the 13 years since passage of the Patriot Act. But the House bill's failings notwithstanding, things could have been worse.

The House Intelligence Committee had championed another "reform" bill that would have actually cemented dragnet N.S.A. surveillance into law. That legislation is now unlikely to move. Importantly, passage of the better House bill also at least gives Congress a platform on which to build, and a chance to pass real surveillance reform.

This is the first time since passage of the Patriot Act that Congress has acted in any way to restrain, rather than expand, foreign intelligence surveillance authority.

The Senate must do several things to improve the current text and ensure the law can't be abused. It should start by shoring up the legal heart of the bill: the definition of the "specific selection terms" that will limit the government's collection of Americans' transactional records from third parties. That definition must be as unambiguous and narrow as possible to prevent the government from seeking "bulky" collection orders that demand records from, for instance, an entire area code or Internet router.

Additionally, senators should impose firm time limits on how long the government can keep any irrelevant records swept up under Patriot Act Section 215. Currently, the bill requires the "prompt" destruction of unneeded records, but given the government's proclivity to stretch the law to its outer bounds and beyond, the lack of a solid deadline may lead to abuse.

The Senate must also ensure that every significant legal opinion of the Foreign Intelligence Surveillance Court — the primary judicial check against the government's misuse of its secret surveillance authorities — is disclosed to the American public. If we've learned anything in the past year, it's that public scrutiny is a powerful corrective to government overreaching, as secret lawmaking and secret adjudication of Americans' privacy are antithetical to the way our democratic system is supposed to work.

Despite its flaws, the House bill still reflects the clear Congressional intent ( with documentary support from the Obama administration ) to end bulk surveillance. That's important. This is the first time since passage of the Patriot Act that Congress has acted in any way to restrain, rather than expand, foreign intelligence surveillance authority. The Senate must now take up the mantle and go even further to protect Americans' privacy rights.