Last week, the Federal Trade Commission announced that it's seeking comment on how to define spam. Currently, the CAN-SPAM Act (PDF) describes a "commercial electronic mail message" as one whose "primary purpose...is the commercial advertisement or promotion of a commercial product or service."

The FTC wants people to comment specifically on how to determine whether a message's "primary purpose" is commercial.

It's a pretty tricky question. For starters, the law already states that alluding to or linking to a commercial entity does not convert an ordinary email into spam. So it's clearly within your rights to send out emails that include a link to the "please donate to the EFF" page in your signature line. But how do we draw the line between an email that is only sort of an ad, and one that is primarily?

EFF's answer to this is simple, and it comes straight out of a decision by the Supreme Court in Riley v. National Federation of Blind of N.C., Inc. (1988). In this case, the court ruled that whenever there is a mixture of commercial and non-commercial speech in a message, then the message is non-commercial for the purposes of First Amendment analysis. Therefore, any email that contains even a portion of non-commercial speech is protected as free speech under the First Amendment.

Having this kind of hard and fast definition is incredibly useful because it protects the broadest possible range of noncommercial speech on the Internet.

It also prevents legitimate speakers from being dragged through expensive court cases on the question of whether a message was "intended" to be commercial or whether a message was "substantially" commercial, two of the potential tests suggested by some. These sorts of subjective tests give trial lawyers a good payday but they leave ordinary people censoring themselves to avoid breaking the rules. By applying the Riley rule to email, we have a clear way to categorize as "commercial" any mail that says something like, "Cialisss i5 gOod bye s0me at this IP-address sucking URL."

Now you can join the EFF in offering the FTC your opinion about how to spot an email with a primarily commercial purpose. Help minimize the collateral damage to legitimate speech on the Internet. Ask the FTC to adopt the Riley rule, submitting your comments via this online form by September 13.