Are anti-spam measures fair?

Spam has been in the news and on many people's minds lately. So my interest was piqued by this inquiry from a reader:

"I'd be very interested in hearing your opinion on the subject of 'Blacklisting' an ISP's non-spamming customers for the purpose of soliciting a negative response from those customers towards the ISP who is viewed as 'spammer friendly' by the blacklisting organization.

"Let me start by saying that I'm an e-mail administrator for a moderate size company, 500 or so users. The company I work for has had its e-mail server blacklisted by an anti-spam organization SPEWS.org [Spam Prevention Early Warning System] solely because it uses AT&T as an ISP.

"From what I've been able to find out, SPEWS.org supposedly identifies a spammer's network (IP address range), blacklists it, and notifies the spammer's ISP. If the ISP does not remove the 'so called' spammer, [SPEWS.org] expands the scope of the blacklisted IP address range to include adjacent networks -- spammer networks or not. This is SPEWS.org's way of forcing AT&T's customers to confront AT&T on their behalf about supposed spammer's residing on its network.

"This is the case with my employer's network. Its IP address range has been blacklisted, along with dozens of other networks, with total disregard for the loss of legitimate e-mail and the consequences that it brings. Luckily the company I work for has multiple Internet connections and therefore has the ability to route e-mail through those connections in order to minimize the effects of SPEWS.org's questionable practices.

"My biggest fear is that the companies, organizations, and ISPs who use these publicly available lists are unaware of the practices used to create the lists. I'm also appalled at the attitude displayed by people in the Usenet newsgroup news.admin.net-abuse.email (NANAE) when I requested our IP address range be removed from the SPEWS list. This is where the SPEWS.org website directs visitors for posting questions, complaints, etc., as [the organization] does not provide contact information on its page."

Now back to my opinion. I have a friend who is a nationally known expert on air filtration. He will delight in telling you that the most efficient air filter is a brick wall. It is 100 percent efficient because no pollutants get through. His point, as you may have guessed, is that what's important in measuring the effectiveness of an air filter is how much clean air gets through -- a measurement known as the Clean Air Delivery Rate. (You should remember this when beguiled by ads for air filters that promise to remove 99.99 percent of pollutants.)

The reason for this little digression into air filters is to draw a comparison between that situation and current spam-blocking techniques. My first reaction to the reader's complaint was that the approach certainly seemed unfair and had the potential to punish the innocent along with the guilty. However, I made a trip to the SPEWS.org Web site and found that the organization's explanations sounded reasonable, if a little drastic. As far as adverse reactions on the newsgroup, nothing will bring out the snarling beast in some people quicker than spam or even a discussion about it. So, beware.

Spam is a growing problem for many individuals and businesses, resulting in lost productivity, rendering some mail systems all but useless, and promising to choke Internet mail communication in the near future -- unless something is done.