It hardly takes a brain surgeon -- or rather a specialist in forensic psychiatry -- to recognize that Norwegian mass murderer Anders Behring Breivik is profoundly mentally ill. His writings, including a 1,500 page manifesto, and his explanations for why he needed to slaughter 77 of his countrymen leave little doubt as to his psychiatric impairment.

The issue of legal insanity is somewhat different, however, from a medical definition of mental illness. Also different are the insanity law and procedures used in Norway as compared to the United States.

According to Norwegian law, a psychotic state of mind at the time of the crime can mitigate criminal responsibility. And, based on a detailed assessment of the accused, including more than a dozen face-to-face interviews with the man, two court-appointed forensic experts have concluded that Breivik was suffering from such paranoid delusions of a psychotic nature that would constitute legal insanity.

I am aware of the often difficult determination about which individuals deserve, through good deed or bad, to be featured on the obituary page. Well, it must have been a really slow day (did death really take a holiday?) for the Globe to include a New York Times story about the passing of Canadian serial killer Clifford Olson.

Few Americans would have recognized Olson’s name or face from the picture that accompanied the story. Arguably, he is (and now was) Canada’s most infamous serial killer of all time -- if not in fact than at least in his own mind. Of course, most people on this side of the border pay very little attention to what goes on in Canada.

The latest report from the Bureau of Labor Statistics appears to have good news with regard to the safety and well-being of American workers. According to preliminary tabulations of occupational fatalities for 2010 (see below), homicides in the workplace declined almost 7% over 2009, continuing a long-term downward trend that began nearly two decades ago. In fact, the 506 workplace homicides for 2010 is the lowest count since these statistics have been collected.

Workplace homicides typically involve robbery -- predominately robberies of convenience stores and taxi drivers for quick cash and quick getaway. These types of episodes have indeed declined substantially in recent years, paralleling the general decline in the overall U.S. homicide rate.

The aggregate figures, although encouraging, obscure a troubling fact: Certain forms of workplace homicide -- fatal assaults by co-workers and especially by customers -- continue to buck the overall downward trend (see below).

Kudos to Norwegian Judge Kim Heger who decided to close his courtroom during the arraignment of the man accused of murdering scores of innocent victims last Friday. The move seems to have frustrated many members of the media and the general public who were eager to hear the defendant describe his motivation and thinking. However, the closed door approach likely disappointed the accused mass murderer even more. After all, he had reportedly been looking forward to the chance to expound on his viewpoint during his initial court appearance.

As details surface in the days and weeks ahead about Friday's massacre in Norway and about Anders Behring Breivik, the man believed to have perpetrated the bloodbath, we will hopefully be able to make some sense of what now seems so unfathomable. However, even with the sketchy information uncovered in the immediate aftermath of the shooting/bombing, the crime and the accused fit the mass murder mold in many respects.

My Northeastern University colleague Jack Levin and I have studied countless mass killings over the past three decades. Certain characteristics are seen time and time again:

At least based on comments uploaded to my "Why mothers kill" blog post of last week, there appears to be some disagreement about whether mothers or fathers are more apt to commit infanticide. The opposing positions are supported by conflicting research reports that use different data sources and different time frames.

There are logical reasons to back either point of view. One might think that fathers are more inclined to kill their children in light of the very uneven gender split generally among those who commit homicide. Overall, 90% of murderers in this country are male.

On the other hand, mothers tend to have much greater contact with their children, increasing the opportunities for violent outbursts directed against their sons or daughters. To whatever extent infanticide is precipitated by the stresses and strains of child rearing, one might expect mothers to outnumber fathers as perpetrators of infanticide.

The grim discovery of 6-year-old Camden Pierce Hughes lying dead on the side of a road in southern Maine and the subsequent arrest of his mother, Julianne McCrery, under suspicion of murder have attracted widespread attention and outrage. In fact, Wednesday’s news of the 42-year-old woman’s capture at a rest stop in Chelmsford, Massachusetts may have eclipsed President Obama’s visit to Boston as the lead story of the day and evening.

If only such cases were as rare as they should be. Regrettably, nearly 100 children ages 5-7 are murdered annually in the United States, and about 20% of these young victims are murdered by their mothers. And this is just the top end of a much larger cluster: There are, on average, about 180 children ages 7 and younger who are murdered each year at the hands of the women who brought them into the world. That’s about one mother-perpetrated infanticide every other day.

It is difficult for most of us to fathom how someone could kill their own flesh and blood, especially a victim so young and innocent. Motherhood is supposed to be about nurturing, not murdering. The motives for such crimes vary from the pathological to the pathetic.

In this space just last week, I wrote critically about a Las Vegas gallery that is planning to exhibit various pieces of artwork produced by John Wayne Gacy and other notorious serial killers. Well, it gets worse: now the Federal Government is getting into the murderabilia business.

Compelled by a court order, the General Services Administration (GSA) today is launching an online auction of personal items that belonged to “Unabomber” Theodore Kaczynski, the reclusive misfit who killed three victims and injured several 23 others during an 18-year-long campaign of murder. Included on the auction block are his driver’s license, birth certificate, academic transcripts and personal checks, which were recovered from the secluded Montana cabin where Kaczynski lived (the same structure that that drew large crowds when displayed at the Newseum in Washington, D.C.)

It is often said that “what goes on in Vegas, stays in Vegas.” Apparently, this isn’t true at the downtown Contemporary Arts Center, where a collection of overpriced and overrated paintings will soon be exhibited and sold to eccentric collectors wishing to take home for display the work of someone infamous. In this case, the artists’ infamy comes not from their artistic talent, but from their ruthless crimes.

At the centerpiece of the upcoming exhibit are dozens of watercolors and drawings by serial killer John Wayne Gacy. Before his capture for murdering 33 young men in suburban Chicago, Gacy had been voted "Man of the Year" by the Jaycees, rubbed elbows with local politicians and was even photographed with first lady Rosalynn Carter. It was the curious paradox of a respected man who secretly killed boys that brought Gacy attention.

Other than the annual struggle to find a thoughtful gift for the mother of my children, and besides the last minute panic when realizing that all the decent “For my Wife” greeting cards have been bought up by other men who planned ahead, the approach of Mother’s Day is a joyous time.  It is, at least in my family.

On occasions like this, I also think about the mothers and their children torn apart by tragedy -- homicide, in particular. I imagine the broken hearts of those mothers whose murdered children will never again buy them a Mother’s Day card, as well as the children of murdered women whose only gift to mom are flowers laid at her grave.

I also think about the mixed emotions of women and their children who spend Mother’s Days within the stark confines of a prison visiting room.  As of 2007, according to the Bureau of Justice Statistics, there were over 65,000 mothers of minor children serving time in state or federal prisons. Alternatively, there were almost 150,000 children under the age of 18 whose mothers were behind bars, a disturbing 122% increase since 1991.

Many Americans, of course, see the plight of incarcerated moms -- being separated from their children, often permanently -- a just punishment for their criminal irresponsibility. Whatever one's sympathies in this regard, we can agree that the truly innocent victims are the children whose mothers are locked away, often permanently, and who must endure the stigma and embarrassment linked to crimes for which they had no responsibility.