US District Court for the Eastern District of Pennsylvania; Judge Jan E. DuBois, September 10, 2004 [ruling that a Pennsylvania law requiring Internet service providers to block websites with child pornography on them is unconstitutional because of its effect on legitimate websites]. Read the opinion here [PDF]. Excerpt:

Although there are strong arguments for the application of strict and intermediate scrutiny, the Court need not choose between the two because, even under the less demanding standard — intermediate scrutiny — the Act does not pass Constitutional muster. Under O'Brien, a regulation must further an important government interest unrelated to the suppression of free expression and the incidental restriction on First Amendment freedoms must be no greater than is essential to the furtherance of that interest. O'Brien, 391 U.S. at 377. The government has the burden of proving that the "regulation will in fact alleviate [the] harms [addressed by the regulation] in a direct and material way,' Turner, 512 U.S. at 664, and it has not met that burden in this case. In addition, the Act suppresses substantially more protected material than is essential to the furtherance of the government's interest in reducing child sexual abuse. Although the prevention of child exploitation and abuse is an state interest unrelated to the suppression of free expression, defendant has not produced any evidence that the implementation of the Act has reduced child exploitation or abuse. The Act does block some users' access to child pornography; however, the material is still available to Internet users accessing the material through ISPs other than the one that blocked the web site. FOF ¶ 109. … Although the inference could be drawn that making it more difficult to access child pornography reduces the incentive to produce and distribute child pornography, this burden on the child pornography business is not sufficient to overcome the significant suppression of expression that resulted from the implementation of the Act

Reported in JURIST's Paper Chase here.