the Psychopathy Checklist: All characterizations of psychopathy in this book were based on the latest research, founded primarily on the work of Dr. Hervey Cleckley and systematically refined by Dr. Robert Hare. Hare's revised Psychopathy Checklist (PCL-R) is used to assess the subject on twenty characteristics, organized into two categories: emotional drivers and antisocial behavior. The twenty are: 1) glib and superficial charm, 2) grandiose estimation of self, 3) need for stimulation, 4) pathological lying, 5) cunning and manipulativeness, 6) lack of remorse or guilt, 7) shallow affect (superficial emotional responsiveness), 8) callousness and lack of empathy, 9) parasitic lifestyle, 10) poor behavioral controls, 11) sexual promiscuity, 12) early behavior problems, 13) lack of realistic long-term goals, 14) impulsivity, 15) irresponsibility, 16) failure to accept responsibility for own actions, 17) many short-term marital relationships, 18) juvenile delinquency, 19) revocation of conditional release, 20) criminal versatility. All characterizations of psychopathy in this book were based on the latest research, founded primarily on the work of Dr. Hervey Cleckley and systematically refined by Dr. Robert Hare. Hare's revised Psychopathy Checklist (PCL-R) is used to assess the subject on twenty characteristics, organized into two categories: emotional drivers and antisocial behavior. The twenty are: 1) glib and superficial charm, 2) grandiose estimation of self, 3) need for stimulation, 4) pathological lying, 5) cunning and manipulativeness, 6) lack of remorse or guilt, 7) shallow affect (superficial emotional responsiveness), 8) callousness and lack of empathy, 9) parasitic lifestyle, 10) poor behavioral controls, 11) sexual promiscuity, 12) early behavior problems, 13) lack of realistic long-term goals, 14) impulsivity, 15) irresponsibility, 16) failure to accept responsibility for own actions, 17) many short-term marital relationships, 18) juvenile delinquency, 19) revocation of conditional release, 20) criminal versatility.

The item titles cannot be scored without reference to the formal criteria contained in the PCL-R Manual. It is issued only to qualified practitioners, who are instructed to combine interviews with case histories and archival data. But in many cases, such as Columbine, the subject is not available for an interview. Studies by outside researchers have concluded that the tool is reliable without the interview in situations where extensive, reliable data is available. Eric left a massive trove, which experts considered far more than enough data to assess him.

Evaluators rate the subject on each trait, assigning a score from 0 to 2: 2 if it clearly applies, 1 if it applies partially or sometimes, 0 if never. The maximum score is 40, and a 30 is required for the designation of "psychopath." There are degrees of psychopathy, but most subjects turn out to be either highly psychopathic or not at all. Average criminals score about 20; they share some behavior with psychopaths but few of the underlying drives.

In 1885: The Oxford English Dictionary The Oxford English Dictionary (1989 edition) cites 1885 as the first time the term (1989 edition) cites 1885 as the first time the term psychopathy psychopathy was used in its present meaning. German researchers used it earlier in the century, with a somewhat different purpose. was used in its present meaning. German researchers used it earlier in the century, with a somewhat different purpose.

Varying definitions: Nothing comparable to the PCL-R exists for Nothing comparable to the PCL-R exists for sociopath, sociopath, though some therapists use the checklist and then assign the subject the designation of "sociopath." though some therapists use the checklist and then assign the subject the designation of "sociopath."

psychopaths and unstable homes: "We do not know why people become psychopaths, but current evidence leads us away from the commonly held idea that the behavior of parents bears sole or even primary responsibility," Hare wrote. But if a child is born with dangerous traits, bad parenting can make him or her infinitely worse. "We do not know why people become psychopaths, but current evidence leads us away from the commonly held idea that the behavior of parents bears sole or even primary responsibility," Hare wrote. But if a child is born with dangerous traits, bad parenting can make him or her infinitely worse.

The family backgrounds of psychopaths turn out to be surprisingly consistent with those of the overall prison population. In both cases, the incidence of significant family problems is high. With nonpsychopathic criminals, a troubled youth correlates closely with the age and seriousness of the first offense. Those with family trouble appear in court by age fifteen, on average. Those without show up nearly a decade later, at twenty-four. Psychopaths arrive earliest of all--at fourteen, on average--and their family background shows no effect on that number whatsoever. But the home life has a huge impact on the type of crime committed by psychopaths. Those from unstable upbringings are far more likely to be violent. In the rest of the prison population, a troubled home seems to drive criminals toward earlier and more serious offenses, but not violence.

screening device for juveniles: It is called the PCL:YV, for "Youth Version." It is called the PCL:YV, for "Youth Version."

stated desire for a career in the Marines: In March 1998, Eric answered the "Career Goals" question on his Diversion questionnaire with "Marine or computer science." In March 1998, Eric answered the "Career Goals" question on his Diversion questionnaire with "Marine or computer science."

Dr. Kiehl repeated: Summaries of Dr. Kiehl's work were based on his published work, as well as phone and e-mail correspondence with me and my researcher. Summaries of Dr. Kiehl's work were based on his published work, as well as phone and e-mail correspondence with me and my researcher.

therapy often makes it worse: This is a widely recognized conclusion. Many studies have confirmed it. One found that convicted psychopaths who took part in therapeutic programs were four times more likely to commit violent crimes than those who did not. This is a widely recognized conclusion. Many studies have confirmed it. One found that convicted psychopaths who took part in therapeutic programs were four times more likely to commit violent crimes than those who did not.

CHAPTER 41. THE PARENTS GROUP.

the FBI organized a major summit: Scenes from the Leesburg summit were described to me by several participants. Quotes were based on their recollections. Scenes from the Leesburg summit were described to me by several participants. Quotes were based on their recollections.

Several of the experts continued: Several continued studying Columbine. Drs. Fuselier, Ochberg, and Hare agreed to several interviews for this book and were of great assistance. Others requested anonymity but continued conferring behind the scenes and provided valuable insights not attributed to any individual. Several continued studying Columbine. Drs. Fuselier, Ochberg, and Hare agreed to several interviews for this book and were of great assistance. Others requested anonymity but continued conferring behind the scenes and provided valuable insights not attributed to any individual.

The Bureau firmly prohibited: All agents were forbidden from speaking about the case, including those at headquarters, such as Mary Ellen O'Toole, who organized the Leesburg summit. All journalists, including me, were rebuffed repeatedly; All agents were forbidden from speaking about the case, including those at headquarters, such as Mary Ellen O'Toole, who organized the Leesburg summit. All journalists, including me, were rebuffed repeatedly; 60 Minutes 60 Minutes sued for information and lost. An exception was made for Agent Fuselier to participate with Jeffco officers in the sued for information and lost. An exception was made for Agent Fuselier to participate with Jeffco officers in the Rocky Rocky's "Inside the Columbine Investigation" series--discussing his role in the investigation, but not his conclusions.

Jeffco commanders were lying: After several years of withholding, Jeffco released documents that proved commanders had been lying on several counts--including repeated denials about possessing the documents. After several years of withholding, Jeffco released documents that proved commanders had been lying on several counts--including repeated denials about possessing the documents.

Investigator Mike Guerra noticed: The actions of Guerra, Kiekbusch, and Searle came from the grand jury report. Guerra described his actions. Searle described actions by her and by Kiekbusch. The actions of Guerra, Kiekbusch, and Searle came from the grand jury report. Guerra described his actions. Searle described actions by her and by Kiekbusch.

Anne Marie Hochhalter: Her progress was drawn from news accounts, particularly Bartels' "A Story of Healing and Hope." Her progress was drawn from news accounts, particularly Bartels' "A Story of Healing and Hope."

Students reached the opposite consensus: The depiction of diverging attitudes among students and parents that spring and summer were based primarily on my numerous interviews and trips to the area at the time and interviews I conducted years later. I also pored over news coverage from the period. The depiction of diverging attitudes among students and parents that spring and summer were based primarily on my numerous interviews and trips to the area at the time and interviews I conducted years later. I also pored over news coverage from the period.

Brian Fuselier was heading: The description of Brian's reactions that summer initially came from my interviews with both his parents; I confirmed them with him several years later. The description of Brian's reactions that summer initially came from my interviews with both his parents; I confirmed them with him several years later.

It was an emotional day: I spent much of the day outside the school, interviewing students coming and going, and observing. I spent much of the day outside the school, interviewing students coming and going, and observing.

"This is not about money!": The description of the Shoelses' press conference was based on my observations. The description of the Shoelses' press conference was based on my observations.

CHAPTER 42. DIVERSION.

their junior yearbooks: Scans of the yearbook pages were released by Jeffco. Scans of the yearbook pages were released by Jeffco.

Eric launched a new charm offensive: Diversion counselors documented each meeting--roughly two a month--which provided a more detailed record of the boys' activity for the last year. Both boys had also acquired day planners by this time, though Dylan used his more. Diversion counselors documented each meeting--roughly two a month--which provided a more detailed record of the boys' activity for the last year. Both boys had also acquired day planners by this time, though Dylan used his more.

His grades dropped briefly: The school released grade reports indicating progress within each semester. For Diversion, the boys were also required to have teachers fill out monthly progress reports, with grade projections and comments. The school released grade reports indicating progress within each semester. For Diversion, the boys were also required to have teachers fill out monthly progress reports, with grade projections and comments.

write apology letters: Jeffco released Eric's letter. Jeffco released Eric's letter.

Then he quit: Months later, Eric would resume using the planner, documenting much of his daily existence. Dylan filled in his planner as well. Jeffco released scans of the full contents of both. Months later, Eric would resume using the planner, documenting much of his daily existence. Dylan filled in his planner as well. Jeffco released scans of the full contents of both.

Dr. Albert switched him: Eric's medications and his responses to them were recorded in his Diversion file. He had completed the switch from Zoloft to Luvox by May 14, 1998. Eric's medications and his responses to them were recorded in his Diversion file. He had completed the switch from Zoloft to Luvox by May 14, 1998.

They got to make movies: Jeffco released many of their videos other than the Basement Tapes. The depictions here were based on my viewing. Jeffco released many of their videos other than the Basement Tapes. The depictions here were based on my viewing.

Eric was gobbling up literature: Eric kept many of his school assignments, including papers on all the items cited in this chapter. I reviewed them all. Eric kept many of his school assignments, including papers on all the items cited in this chapter. I reviewed them all.

CHAPTER 43. WHO OWNS THE TRAGEDY.

There is a house, outside of Laramie: Linda described their retirement plans, including the house, in an interview with me. Linda described their retirement plans, including the house, in an interview with me.

Columbine was set to reopen: I attended the Media Summit and the Take Back the School rally. Only pool reporters were permitted inside the human shield at the rally, so I relied on their briefings for that passage, as well as my later interviews with numerous people inside. I discussed objectives for the rally and the ideas behind it with several administrators responsible for designing it. I attended the Media Summit and the Take Back the School rally. Only pool reporters were permitted inside the human shield at the rally, so I relied on their briefings for that passage, as well as my later interviews with numerous people inside. I discussed objectives for the rally and the ideas behind it with several administrators responsible for designing it.

For one morning: I spent the morning in the Columbine commons, chatting with the kids as they painted their tiles. I spent the morning in the Columbine commons, chatting with the kids as they painted their tiles.

CHAPTER 44. BOMBS ARE HARD.

just before Halloween: From this point, Eric recorded the dates for all major milestones, as well as a slew of trivial ones. He also kept dated receipts for many of his purchases. From this point, Eric recorded the dates for all major milestones, as well as a slew of trivial ones. He also kept dated receipts for many of his purchases.

began assembling his arsenal. Eric let Nate watch him produce part of one batch. Nate described the process to police; their records served as the basis for my visual depiction. Eric let Nate watch him produce part of one batch. Nate described the process to police; their records served as the basis for my visual depiction.

CHAPTER 45. AFTERSHOCKS.

Milestones were hard: I covered most of the events in this chapter for I covered most of the events in this chapter for Salon Salon and the bulk of the material was based on that reporting. (An exception was the football championship--I followed the team's progress but did not attend the games.) Years later, I gathered hundreds of pages of news stories on the events and mined them for additional quotes, including those from the Graves and Hochhalter families. All news quotes are cited in the expanded Web version of this Notes section. and the bulk of the material was based on that reporting. (An exception was the football championship--I followed the team's progress but did not attend the games.) Years later, I gathered hundreds of pages of news stories on the events and mined them for additional quotes, including those from the Graves and Hochhalter families. All news quotes are cited in the expanded Web version of this Notes section.

another publication broke the news: It was my story in It was my story in Salon Salon.

The magazine ran an expose: Time Time sent a team back to reinvestigate the tragedy and reexamined the entire case for that cover story. It did a great job, effectively correcting the major myths. But it did not cop to the correction. This was a grievous example of "rowback"--the term was resurrected in 2004 by sent a team back to reinvestigate the tragedy and reexamined the entire case for that cover story. It did a great job, effectively correcting the major myths. But it did not cop to the correction. This was a grievous example of "rowback"--the term was resurrected in 2004 by New York Times New York Times public editor Daniel Okrent to critique Iraq War coverage; it's rarely heard even within the industry, because it denotes such an ugly sin. Okrent cites journalism educator Melvin Mencher describing it as "a story that attempts to correct a previous story without indicating that the prior story had been in error or without taking responsibility for the error." Okrent wrote that a more candid definition might be "a way that a newspaper can cover its butt without admitting it was ever exposed." public editor Daniel Okrent to critique Iraq War coverage; it's rarely heard even within the industry, because it denotes such an ugly sin. Okrent cites journalism educator Melvin Mencher describing it as "a story that attempts to correct a previous story without indicating that the prior story had been in error or without taking responsibility for the error." Okrent wrote that a more candid definition might be "a way that a newspaper can cover its butt without admitting it was ever exposed."

CHAPTER 46. GUNS.

Eric named his shotgun: Arlene was the heroine from the Arlene was the heroine from the Doom Doom books Eric enjoyed. He scratched the word into her barrel and referred to her by name in writings and on video. books Eric enjoyed. He scratched the word into her barrel and referred to her by name in writings and on video.

Eric fit both categories: Millon, Simonsen, Davis, and Birket-Smith created the ten subcategories to sort out very different types of psychopaths, but they are not designed to be mutually exclusive; nor are they necessarily the drivers of behavior. Eric exhibited symptoms consistent with malevolent and tyrannical personalities, and Dr. Fuselier concurred that Eric appeared to be a cross between those two. Millon, Simonsen, Davis, and Birket-Smith created the ten subcategories to sort out very different types of psychopaths, but they are not designed to be mutually exclusive; nor are they necessarily the drivers of behavior. Eric exhibited symptoms consistent with malevolent and tyrannical personalities, and Dr. Fuselier concurred that Eric appeared to be a cross between those two.

"I want to tear a throat out": I edited this passage down. It went on much longer, and more viciously. I edited this passage down. It went on much longer, and more viciously.

On January 20: The Diversion program files cite February 3 as the termination date, but that's not an accurate reflection, particularly from the boys' perspective. In both files, Kriegshauser documented meeting with them on January 20 to close their cases. The Diversion program files cite February 3 as the termination date, but that's not an accurate reflection, particularly from the boys' perspective. In both files, Kriegshauser documented meeting with them on January 20 to close their cases.

Eric was also working hard: Eric wrote about his efforts to "get laid" frequently during the final months. Eric wrote about his efforts to "get laid" frequently during the final months.

CHAPTER 47. LAWSUITS.

Mr. D told a magazine: He said it to me. I covered the events of this chapter extensively for He said it to me. I covered the events of this chapter extensively for Salon, Salon, and most of it was based on that reporting. and most of it was based on that reporting.

the Rohrboughs: For simplicity, I used "the Rohrboughs" periodically to denote both sides of Danny's family, the Rohrboughs and Petrones. For simplicity, I used "the Rohrboughs" periodically to denote both sides of Danny's family, the Rohrboughs and Petrones.

gun-control legislation: In April 2000, a few bills were pending to allow concealed weapons in Colorado. Those were quickly defeated in the wake of the tragedy. In April 2000, a few bills were pending to allow concealed weapons in Colorado. Those were quickly defeated in the wake of the tragedy.

CHAPTER 48. AN EMOTION OF GOD.

a big problem: Eric cited getting the bombs in as a major issue. Eric cited getting the bombs in as a major issue.

If only he had a little more cash: Eric expressed frustration about his limited funds and drew up budgets for his arsenal. Eric expressed frustration about his limited funds and drew up budgets for his arsenal.

Dylan wrote a short story: Jeffco released the story, with Judy Kelly's notes. Jeffco released the story, with Judy Kelly's notes.

Three friends went with them: The boys videotaped quite a bit of the target practice, and Jeffco released the tape. The boys videotaped quite a bit of the target practice, and Jeffco released the tape.

They made three target-practice trips: Manes told lead investigator Kate Battan they made three trips, but she could not determine whether they were before or after the videotaped trip. Manes told lead investigator Kate Battan they made three trips, but she could not determine whether they were before or after the videotaped trip.

Dylan leaked again: Zack told police his conversation with Dylan occurred in February. His memory might have been off slightly, or Dylan might have begun training earlier--with or without Manes. Zack told police his conversation with Dylan occurred in February. His memory might have been off slightly, or Dylan might have begun training earlier--with or without Manes.

Desperado: Robert Rodriguez directed the film. Tarantino appeared as an actor and is closely associated with Rodriguez. Robert Rodriguez directed the film. Tarantino appeared as an actor and is closely associated with Rodriguez.

CHAPTER 49. READY TO BE DONE.

Most of the Parents Group attended: The scenes at the opening of the atrium came from my observations. The scenes at the opening of the atrium came from my observations.

Jeffco was forced to cough up: I followed the slow release of the information over several years and examined most items as they came out, but I did not write about these events at the time. I followed the slow release of the information over several years and examined most items as they came out, but I did not write about these events at the time. Westword Westword and the and the Rocky Rocky did an excellent job covering the slow trickle, and I relied on their work. I considered the reports from the Colorado attorney general and the grand jury definitive. did an excellent job covering the slow trickle, and I relied on their work. I considered the reports from the Colorado attorney general and the grand jury definitive.

the affidavit to search Eric's house: After months of silence, the DA responded to a written request from the Browns. His response letter alluded to Guerra's affidavit, which for two years his agency had insisted did not exist. Randy and Judy couldn't believe it. They took it to CBS, and After months of silence, the DA responded to a written request from the Browns. His response letter alluded to Guerra's affidavit, which for two years his agency had insisted did not exist. Randy and Judy couldn't believe it. They took it to CBS, and 60 Minutes 60 Minutes cornered Thomas. Judge Jackson demanded to see it--it had been withheld from him as well. cornered Thomas. Judge Jackson demanded to see it--it had been withheld from him as well.

The affidavit was more damning: Guerra was exceptionally convincing. He demonstrated motive, means, and opportunity. From a threat-assessment perspective, the specificity of Eric's attack raised it to high risk. The details regarding the weaponry increased it further. The capstone, though, came in connecting Eric's plans to physical evidence. The affidavit described the pipe bomb found near Eric's home and stated twice that it matched his descriptions of "Atlanta" and "Pholus." Guerra was exceptionally convincing. He demonstrated motive, means, and opportunity. From a threat-assessment perspective, the specificity of Eric's attack raised it to high risk. The details regarding the weaponry increased it further. The capstone, though, came in connecting Eric's plans to physical evidence. The affidavit described the pipe bomb found near Eric's home and stated twice that it matched his descriptions of "Atlanta" and "Pholus."

"Based on the aforementioned information your affiant respectfully requests the court issue a search warrant for the residence," Guerra's affidavit concluded. The police would have found a great deal. Eric had made quite a few bombs by that time. The former chief justice of the Colorado Supreme Court, who had chaired a commission set up by the governor to investigate Columbine, eventually weighed in. He chided Jeffco for missing a "massive" number of clues. The massacre could have been prevented, he concluded. He lamented the perimeter response; if the SWAT team had stormed the building, he said, several lives could have been saved.

The affidavit also revealed that Division Chief Kiekbusch had told at least three whopping lies at the press conference ten days after Columbine: that the Browns had not met with Investigator Hicks, that the department couldn't find bombs like those in Eric's Web descriptions, and that it had been unable to locate his Web postings. The affidavit contradicted all three, and Kiekbusch had to have been familiar with it, since he had just attended the Open Space meeting with one topic: how to suppress it.

Jeffco responded with new lies. It issued a press release claiming it had disclosed the affidavit's existence a few days after Columbine--at the very time commanders were meeting to plot how to hide it. All the local media called Jeffco on the lie.

"It's amazing how long": Sue Klebold recalled this exchange to David Brooks in 2004. He reported it in his Sue Klebold recalled this exchange to David Brooks in 2004. He reported it in his New York Times New York Times column. column.

The FBI and Secret Service: The FBI released its report, The FBI released its report, The School Shooter: A Threat Assessment Perspective, The School Shooter: A Threat Assessment Perspective, in 2000. Two years later, the Secret Service and the Department of Education teamed up for a broader analysis: in 2000. Two years later, the Secret Service and the Department of Education teamed up for a broader analysis: The Final Report and Findings of the Safe School Initiative. The Final Report and Findings of the Safe School Initiative. Both reports were excellent, and I relied on them extensively. I also used news accounts to document foiled copycats in other cities. I interviewed school administrators, students, and mental health experts about zero tolerance policies. Both reports were excellent, and I relied on them extensively. I also used news accounts to document foiled copycats in other cities. I interviewed school administrators, students, and mental health experts about zero tolerance policies.

two biggest myths: The Secret Service studied every targeted attack at schools from December 1974 to May 2000. There had been forty-one attackers in thirty-seven incidents. Disciplinary history and academic performance also varied widely. The loner myth was perhaps the single biggest misconception. Some of the attackers were loners; two-thirds were not. The Secret Service studied every targeted attack at schools from December 1974 to May 2000. There had been forty-one attackers in thirty-seven incidents. Disciplinary history and academic performance also varied widely. The loner myth was perhaps the single biggest misconception. Some of the attackers were loners; two-thirds were not.

they "snapped": "Nonviolent people do not 'snap' or decide on the spur of the moment to meet a problem by using violence," the FBI report said. Planning ranged from a day or two in advance to over a year. "Nonviolent people do not 'snap' or decide on the spur of the moment to meet a problem by using violence," the FBI report said. Planning ranged from a day or two in advance to over a year.