School shootings: malignant, contagious social meme?

I've been trading emails with Loren Coleman lately about the rash of school shootings in recent weeks. On September 14, Canadian Kimveer Gill attacked. He was said to have had a fondness for the Columbine shooters (he certainly loved the game). A number of similarly of deadly incidents followed, right up to today's death spree at an Amish school in Pennsylvania. Seems like a lot in a short period of time. Coincidence, or social phenomenon?

Coleman is a suicide prevention and school violence researcher and consultant, and author of Suicide Cluster (1987) and The Copycat Effect (2004). He writes:

Here is what I am finding:

* Most contemporary school shootings tend to occur primarily during two periods of the school year - at the beginning (late Aug through October) and near the the end of the academic year (March-April).

* Copycats follow a regular temporal pattern that repeats - these could be after a primary media event in a day, a week, two weeks, a month, a year, ten years - vulnerable humans have internal media clocks.

* Copycats imitate the previous violent attacks, oftentimes down to specific details as that mirror the previous specifics of the shooter, the victims, and the methods.

* "Celebrity" events have a far-reaching impact and modeling effect -- so, of course, Columbine serves as a dark cloud over many school shootings.

One of the silliest things I have heard from cable news in the last several days during mid-September 2006, is that "these school shootings aren't like the other school shootings." This is short-sighted, and factually untrue.

Before the current model (post-1996) in which a member of the student body would go into their own school and kill fellow students, the pattern was one of outsiders -- often adults -- going into schools and killing students. In my book, I discuss some of the more infamous cases (...). Every year is different, and a fresh view must be considered based upon observations that are right in front of our eyes. What I do at the beginning of a new school year is to see if there is an emerging pattern that will be the re-worked "copycat" model for the new school year. To me, it was and is obvious where we were going this year.

Here's what I see: a mix of outsiders invading school, and students making plans too (...)

Link to the website for Coleman's "Copycat Effect" book, with the full text of this essay. Here's a related post on his blog, in which he predicts more shootings in October as the social contagion spreads during this present cycle. Here's a related news item: "Six school shootings in less than six weeks: experts comment on cluster," in Canadian Press.