As the House Judiciary Committee met to consider changes to the Stop Online Piracy Act, several members of the committee warned that rushing the bill through the legislative process would lead to costly mistakes.

"I cannot fathom why we are moving so quickly on a bill that could cause us to save billions of dollars or lose billions of dollars," said Rep. Sheila Jackson Lee (D-TX). "All of us are opposed to online piracy," she said, but she urged the committee to take more time to address critics' objections.

Rep. Darrell Issa (R-CA) agreed. He pointed to the America Invents Act, an overhaul to the patent system that was six years in the making. "We haven't done our due diligence," he said.

The Judiciary Committee gathered on Thursday to consider amendments to SOPA and prepare the bill for consideration by the full House. Several members pointed out that the committee didn't hear from any technologists at last month's hearing on the bill. The line-up at that hearing consisted of five bill supporters and a lawyer from Google, which is opposed to the bill. None of the other groups who have expressed concerns—technologists, high-tech investors, legal scholars—have had an opportunity to address the committee.

But the criticisms did not seem to sway Lamar Smith, the committee chairman and the bill's sponsor. He urged compromise, persuading the sponsor of the first amendment to withdraw it and instead work with his staff on a compromise.

One of the sharpest moments of controversy came when Rep. Jared Polis (D-CO) offered an amendment exempting universities and non-profits from the obligation to participate in the DNS blacklist provisions. This sparked a lengthy argument with Rep. Mel Watt (D-NC), who insisted the provision was unnecessary because judicial oversight would be sufficient to avoid abuses. "The judge isn't stupid," Watt said.

But Watt seemed not to fully understand how either SOPA or Polis's amendment worked. At one point he asked Polis to clarify whether his amendment would allow universities and non-profits to host infringing content on their websites. Polis pointed out that this wasn't the amendment's focus at all. Rather, his amendment was designed to avoid imposing on these organizations the costs of implementing a DNS blacklist, which he described as an unfunded mandate.

Polis's amendment was defeated by the committee.

The session is likely to be a long one. Early in the hearing, Chairman Smith asked for unanimous consent to skip reading the bill aloud. But Rep. Zoe Lofgren (D-CA), a fierce opponent of the proposal, insisted that a clerk read the whole thing—a process that took about an hour. With that kind of acrimony, the Committee is likely to be working late into the night.