A federal judge in Philadelphia yesterday blocked a law designed to protect minors from sexually explicit commercial sites on the World Wide Web on the grounds that it would restrict constitutionally protected speech. "{P}erhaps we do the minors of this country harm if First Amendment protections, which they will with age inherit fully, are chipped away in the name of their protection," wrote U.S. District Judge Lowell A. Reed Jr. in a strongly worded opinion. "Despite the Court's personal regret that this preliminary injunction will delay once again the careful protection of our children, I without hesitation acknowledge the duty imposed on the Court and the greater good such duty serves," wrote Reed, who was appointed to the bench in 1987 by then-President Ronald Reagan. Reed's order imposed a preliminary injunction against the Child Online Protection Act (COPA) and stopped the law from taking effect at midnight Monday, when a temporary restraining order he had granted in November would have expired. "Naturally, we're delighted by the decision," said Christopher A. Hansen, staff counsel for the American Civil Liberties Union, which is leading a coalition of groups challenging the law. "We've always said these cases are about speech. . . . The government kept arguing that these cases are about dollars and cents." Reed made the distinction explicitly -- and came down on the side of speech. The Web sites deserved the highest possible level of protection by the courts "not because of the risk of driving certain commercial Web sites out of business, but the risk of driving this particular type of protected speech from the marketplace of ideas." Supporters of the bill urged the government's lawyers to fight on. "We continue in our steadfast support of the Child Online Protection Act, and we urge the Department of Justice to continue defending this law at trial or on appeal all the way to the U.S. Supreme Court," said COPA author Rep. Michael G. Oxley (R-Ohio), co-sponsor Rep. James C. Greenwood (R-Pa.) and House Commerce Committee Chairman Thomas J. Bliley (R-Va.). "Traditional laws for minors at the state level have worked effectively to protect children from raw pornography without limiting adults' free expression or access to legal materials," they said. "Through COPA we seek only to apply the same common-sense standard to the World Wide Web as prevails in the rest of our free democratic society." Chris Watney, a spokeswoman for the Justice Department, said only that government lawyers "are reviewing the judge's decision." The injunction means that the government will not be able to enforce the law until the challenge to it can be heard and decided. Such injunctions are granted on the likelihood that the challenge on the merits will be successful, so their language is read carefully for subtle clues to a court's views. The COPA bill is the second major attempt by Congress to protect children from adult materials found online. The first, the Communications Decency Act, was passed in 1996 and struck down in 1997 by the Supreme Court as unconstitutional. That bill made it a crime to make "indecent" or "patently offensive" material available to minors via computer networks. In that case, Justice John Paul Stevens wrote that the 1996 law "threatens to torch a large segment of the Internet community" because the law was overly vague and would unduly infringe on the speech rights of adults in the name of protecting children. "The interest in encouraging freedom of expression in a democratic society outweighs any theoretical but unproven benefit of censorship," Stevens wrote. The Child Online Protection Act, passed last November, was designed to be more narrow. Instead of trying to regulate the entire Internet and its patchwork of varied technologies, it focuses solely on commercial Web sites. The law requires purveyors of materials "harmful to minors" to take steps to keep minors from accessing their sites, such as requiring a credit card number for entry. Those found guilty of violating COPA could be forced to pay hundreds of thousands of dollars in fines and be imprisoned for up to six months. Reed wrote that in fact nothing in the law limited its application to commercial pornographers and noted that the government's requirement of some form of adult identification could drive people away from the burgeoning medium and impose too high a burden on many Web site owners. The government, Reed wrote, had not argued persuasively that COPA represented the least restrictive means of protecting minors from objectionable online material. "The record before the Court reveals that blocking or filtering technology may be at least as successful as COPA would be in restricting minors' access to harmful material online without imposing the burden on constitutionally protected speech that COPA imposes on adult users or Web site operators," Reed wrote. Roberta Speyer, publisher of obgyn.net, an internationally recognized site for obstetricians, gynecologists and their patients and one of the parties to the suit, said many doctors from such countries as Namibia and El Salvador may not even have credit cards. "There's people who frankly don't want to give a credit card, especially if they're not buying anything." Much of the material on obgyn.net is sexually explicit, said Speyer, who runs the advertising-supported service with her husband out of their Austin, Tex., home. If the law were upheld, "I would have to move my server out of the country."