AT&T and other telecommunications companies are being sued for allegedly allowing federal au ­ thorities to tap phone lines for years without a warrant. President George W. Bush wants Congress to grant the companies retroactive immunity, and the Senate has agreed. But I think such a grant of blanket immunity would be a big mistake.

To be sure, this is a thorny issue that pits concerns over civil liberties and privacy against national security and government secrecy. Available information says the government wanted the wiretaps to catch communications with overseas terrorists shortly after 9/11. And certainly it was a frantic, desperate time. But the whole point of laws is to ensure that we--and more important, our government--act with regard for both safety and essential freedoms at just such periods. So you should care about how these cases are settled.

Here's the main issue: Class-action lawsuits claim the companies broke the law by allowing the government to implement wiretaps without a warrant or special certification. The companies say they acted in "good faith"--and there's no denying that they acted in response to requests from the highest levels of government.

Was the surveillance legal, though? Under existing wiretapping law, companies have legal cover against lawsuits when they receive a warrant or a certification from the attorney general. But the administration has classified any such documents that they may have given the companies as "state secrets," preventing the firms from showing them. So the Senate Select Committee on Intelligence, which reports it has reviewed letters given to the companies by the administration, says the businesses involved should re ­ -ceive retroactive immunity because they can't properly defend themselves. That kind of catch-22 logic concerns me.

For the sake of argument, let's say sensitive information in these seven-year-old documents could hurt current surveillance efforts. Luckily, a rival bill passed by the House has a solution.

The House bill says the businesses involved can present a received certification, letters, or other documents in a secret session before a judge, without the plaintiffs present. If, as the Senate report states, letters and documents given to the telephone companies "stated that the activities had been determined to be lawful by the Attorney General," then a judge could consider that a strong defense, and companies would likely and justifiably escape penalty.

But if one or more of these companies broke the law and handed over our data without a warrant or legal certification, they should be held accountable. These weren't emergency wiretaps to forestall an immediate threat (in which case existing legal provisions allow the government to wiretap right away and get a warrant afterwards), but were longstanding surveillance programs. Company lawyers likely knew the legal ramifications of these programs by heart and had plenty of time to either request and receive a warrant or certification, or refuse the request. (One company--Qwest--says that it did refuse when the government didn't offer a warrant.)

Congress may debate these bills for some time, but we need to get to the bottom of this and determine whether these companies that are custodians of our communications are doing what they are legally obligated to do to protect our privacy. And if these companies broke the law and handed over our data without legal justification, they should pay.

I think the courts are exactly the right place for that determination.