1997),[2] is a case in which the United States Court of Appeals for the Fourth Circuit determined the immunity of Internet service providers for wrongs committed by their users under Section 230 of the Communications Decency Act.

Section 230 was enacted, in part, to maintain the robust nature of Internet communication ...[4]On April 25, 1995, six days after the Oklahoma City bombing, a message was anonymously posted on the America Online (AOL) "Michigan Military Movement" bulletin board advertising items with slogans glorifying the bombing of the Alfred P. Murrah Federal Building.

[5] After the removal of the message, however, another anonymously posted advertisement stated that the shirts had "SOLD OUT" and that items with new slogans had been made available.

At this point, per AOL's recommendation, Zeran contacted the Federal Bureau of Investigation; however, for the next week, new messages continued to appear.

[7] At this point, Zeran's house was placed under protective surveillance, and he was unable to use his telephone for his home business, as the threatening calls were coming in approximately every two minutes.

In response to this claim, AOL argued that Section 230, which was passed in 1996, preempted the New York ruling, which was issued in 1991 and based on that state's law at the time.

[5] The questions at issue in the lower court ruling were determined to be: (1) whether the CDA preempts a state law negligence claim against an interactive computer service provider ... and

The court found, however, that distributors are a subset of publishers, and that as a result Section 230 conflicted with the state defamation law, thus preempting it.

[5]Since distributor liability would have the effect of disincentivizing the filtering of content by third parties, the court found that such laws were in conflict with the "purpose and objectives of congress," and were thus preempted.