Restricting unsolicited faxes is found constitutional.

In a decision that could affect challenges to spam, a federal appeals court has ruled that a law restricting junk faxes was constitutional. This sets a precedent that could help legal attempts to restrict unsolicited commercial e-mail, said experts said in news reports.

The Eighth Circuit Court of Appeals reversed a lower court's ruling and said that a 1991 federal law banning unsolicited fax advertising did not violate the First Amendment's guarantee of freedom of expression.

The three-judge panel also said that "there is a substantial government interest in protecting the public from the cost of shifting and interference caused by unwanted fax advertisements," which consume the recipient's ink, toner and paper.

A similar argument is made about spam because companies have to spend money on e-mail filtering systems and heftier bandwidth to handle the volume of unsolicited e-mail.

The matter before the appeals court involved two consolidated cases. The State of Missouri had sued American Blast Fax Inc. and Fax.com Inc. for violating statutes against unsolicited fax advertising. The district court held that the part of the Telephone Consumer Protection Act of 1991, which related to the case violated the First Amendment Guarantee of freedom of speech and dismissed the action.