1. What motivated you to delve into the life story of Derek Boogaard?

Derek Boogaard, a 6-foot-8, 28-year-old hockey enforcer with the New York Rangers, was considered one of the toughest men in the sport before he died of an alcohol-and-painkiller overdose on May 13. His family donated his brain to science. That combination of details—an oversized reputation as a tough guy, an overdose involving painkillers and the burgeoning science of brain trauma—was more than enough to capture our fullest attention. Add in other parts to Boogaard’s background, including being raised by a Canadian Mountie in small-town Saskatchewan, the prevalence of hockey in Canadian culture and the endless debate about fighting in the sport, and we were quickly devoted to exploring the story.

2. The New York Times spent over 6 months on this series. Was it difficult to sell your bosses on an in-depth posthumous investigation of a hockey enforcer?

They mostly had to sell me. I’m used to parachuting into places, spending a couple days and leaving with a 1,000-word story. That is my usual metabolism. In this case, Sports Editor Joe Sexton simply asked me to spend some time—no deadline—exploring Boogaard’s life. After a couple of weeks, we realized there was the potential for a fascinating story, and Joe was committed to doing it right.

3. How is fighting institutionalized within the National Hockey League, and how does the NHL’s stance on fighting differ from other professional sports leagues?

Fighting has been part of hockey since its inception, before the NHL was founded. It was, and is, seen as an outlet (or a “thermostat,” to use NHL Commissioner Gary Bettman’s word) for high-speed violence that sometimes takes place during a game. In most sports leagues, simply throwing a punch at an opponent leads to immediate ejection and the likelihood of suspensions and fines. In the NHL, and even most of the junior leagues and minor leagues that feed into it, it is usually punished by 5 minutes in the penalty box for both combatants.

4. What is chronic traumatic encephalopathy (CTE), and how did the disease contribute to Boogaard’s cognitive and emotional decline?

In very general terms, it is a sort of cousin to Alzheimer’s disease, with similar symptoms: memory loss, impulsiveness, confusion, impaired judgment, aggression and depression. CTE is caused by repetitive head trauma, not all of which have to be as severe as concussions. For decades, it was considered a disease for boxers, but recent research has found CTE (only diagnosed posthumously) in the brains of several dozen former NFL players and, in the past two years, four former NHL players. Boogaard showed most of the symptoms during his final couple of years. But his symptoms coincided with his abuse of drugs (painkillers, mostly), so researchers are unable to determine precisely how much of his downfall was connected to CTE.

5. Diminished impulse control is a hallmark of CTE, and many psychiatrists classify addictions as disorders of impulse control. Could Boogaard’s head trauma have predisposed him to addiction or overdose by impairing his ability to regulate his drug intake?

Yes, it’s possible. His symptoms, though, seemed to kick in during his final two years of life, which is a hallmark of CTE. But because they kicked in at the same time he was seriously abusing drugs, scientists are reluctant to say whether CTE played a role in his addictiveness. It’s a chicken/egg thing.

6. What effect does the NHL’s fighting culture have on the thousands of kids who play hockey?

Hockey enforcers have long been among the most popular players, because they are seen as blue-collar guys willing to put their bodies on the line for little glory. Their place in culture is cemented in movies such as “Slap Shot” and many web sites devoted to hockey fighting. Young hockey players are quick to idolize these players as well, and sometimes start imitating them at the earliest stages. At the “juniors” level—ages 16 and over—fighting is a big part of the game (more than it is in the NHL). Some junior-level fighters are scouted in their early teens, when their size and toughness sets them apart. Like Boogaard and others who do not possess the normally necessary hockey skills, they are routed onto a different track toward professional hockey.

7. Do you see cultural attitudes towards concussions in contact sports changing?

Attitudes have changed a great deal in recent years, and I’d give substantial credit to The New York Times and my colleague Alan Schwarz, who wrote hundreds of stories about concussions and CTE, mostly centered on the NFL and its initial reluctance to address the issue in a serious manner. As more and more former athletes are found to not only have had CTE, but have also suffered its effects, the awareness of the issue, from the pro level to the lowest levels of recreational sports, has grown dramatically.

8. Will the NHL go the way of the NFL and formally acknowledge the link between concussions and dementia?

The researchers at Boston University, who are at the forefront of the brain-trauma research, said it took about eight deceased former players with CTE before the NFL took the matter seriously and acknowledge the impact of concussions. The NHL now has been presented four such cases of former NHL players. The question now is how many more have to come to light before the league takes a tougher stance on fighting.

9. Should the NHL adopt a real zero tolerance policy towards fighting, like you see in international competitions and college hockey?”

Most North American pro leagues (as well as the amateur junior leagues, for 16 and older) follow the lead of the NHL. You might argue that those lower leagues are more dependent on fighting as a fan draw than the NHL, which can showcase its top-tier talent. Fighting does not occur, for the most part, in college hockey or in international competition. By the way, the NHL is quick to point out that fighting is not “allowed,” because it is penalized. The question is, should it be penalized more severely in order to diminish its role?