Jillian Peterson, a criminologist, answers a range of true‑crime questions:
- **Spouse as suspect:** About 35‑50% of murdered women are killed by a current or former spouse/partner, making the spouse the most likely suspect once other motives (robbery, drugs, gangs) are ruled out.
- **Clearance rates:** The U.S. murder clearance rate is only ~50%; roughly 1% of cold cases are solved, a figure that has fallen as homicide numbers rose while police staffing declined.
- **Jack the Ripper:** He existed and committed a series of gruesome murders in 1888 Victorian England; another contemporary killer, Thomas Cream, was active but could not have been the Ripper.
- **Citizen sleuthing:** Amateur investigators (often inspired by podcasts or social media) can help locate missing persons—as in the Gabby Petito case—but police warn they may accuse innocents and hinder investigations.
- **Why serial killers kill:** Three main motives emerge:
1. **Power/control** (e.g., Zodiac Killer).
2. **Sexual fantasy** (e.g., Ted Bundy).
3. **Hallucinations/delusions** (e.g., Son of Sam). Brain studies show differences in the amygdala, though causality is unclear.
- **COVID‑19 homicide spike:** Homicide rose ~30% during the pandemic, driven by financial strain, stress, and a pull‑back of policing (“de‑policing”) after events like George Floyd’s murder.
- **U.S. murder rate:** At 4.38 per 100 k residents, the U.S. exceeds most similarly developed nations (Europe, Canada, Australia) but is not the world’s highest; some Latin American countries have higher rates.
- **Psychopathy vs. sociopathy:** Psychopathy is the clinically tested construct used today; “sociopath” is an older, less precise term largely relegated to pop culture. Psychopaths can conceal their traits; a subtle clue may be difficulty reading or mimicking others’ emotions without feeling them.
- **Guns and murder:** Gun homicide rates fell in the 1990s despite rising gun ownership, then climbed again in recent years; the U.S. now has more guns than people, with ~120 gun‑related deaths per day (including suicides, accidents, police shootings).
- **Missing persons:** Roughly half a million people are reported missing each year in the U.S.; about 90% are runaways, leaving ~50 k unaccounted for annually.
- **Mass shooters:** 98% are male; ~91‑92% are current or former students of the school they attack, often coming from violent, abusive homes and seeking notoriety.
- **School shootings:** Perpetrators typically plan them as final acts, wanting to be remembered; they target their own school because it holds their grievance.
- **Murdoch case:** Highlights how a suspect with local status can impede an independent investigation in a small community.
- **CSI effect:** TV crime shows raise jurors’ expectations for forensic evidence, influencing acquittals, but there is little evidence that criminals learn from these shows to avoid detection.
- **Most prolific U.S. serial killer:** Samuel Little confessed to killing over 90 women (sex workers, drug users, homeless) from ~1970‑2005; his DNA later linked him to many of the murders.
- **Typical jobs of serial killers:** Over‑represented occupations include mechanics, machinists, truck drivers, and police officers—roles that may facilitate crime or evasion.
- **Female serial killers:** Though rare, many are nurses who use poison; their medical access helps them avoid detection for long periods (e.g., British nurse who killed seven newborns, Kristen Gilbert).
- **Age of onset:** Serial killing usually begins in the mid‑to‑late 20s, later than other forms of violence.
- **Zodiac Killer:** Active in Northern California in the 1960s; he sent taunting letters and complex ciphers (one solved only in 2020) but was never identified or convicted.
- **Marriage proposals to incarcerated killers:** High‑media cases attract many letters from women drawn to the danger and notoriety of the offender.
- **Family annihilations:** About 10‑20 per year involve a man killing his spouse, children, and then himself; they are linked to histories of domestic violence, suicidality, and a desire for control.
- **Jeffrey Dahmer’s cannibalism:** Interpreted as an extreme expression of dominance and control, or alternatively as a desperate attempt to feel close to victims due to profound loneliness.
- **Ted Bundy today:** Modern technology (ubiquitous phones, GPS, DNA, surveillance) would likely prevent a Bundy‑style killing spree from succeeding.
- **Missing hikers:** Many disappearances are accidents, but some result from opportunistic offenders; the “routine activity” framework (motivated offender, suitable target, lack of guardianship) explains why remote trails are vulnerable.
Overall, Peterson covers statistical trends, psychological motives, investigative challenges, and the influence of media and technology on both crime and its perception.
1. Jillian Peterson is a criminologist and former investigator.
2. 35‑50% of women who are murdered are killed by a current or former spouse or partner.
3. The country’s murder clearance rate is about 50%.
4. Only about 1% of cold cases are solved.
5. Jack the Ripper existed and committed a series of violent gruesome murders.
6. Thomas Cream was convicted of poisoning nine or ten people during the same period as Jack the Ripper.
7. Thomas Cream’s rumored final words were “I am Jack…”, though he was in prison at the time of some of the murders.
8. “Citizen sleuth” refers to individuals using podcasts or social media to try to solve crimes.
9. In the Gabby Petito case, TikTok users helped locate her body.
10. Police often dislike citizen sleuth efforts because they can lead to false accusations of innocent people.
11. Serial killer motivations fall into three categories: power/control, sexual fantasy, and hallucinations.
12. An example of a power/control serial killer is the Zodiac Killer, who attacked young couples.
13. An example of a sexual‑fantasy motivated serial killer is Ted Bundy.
14. An example of a hallucination‑motivated serial killer is the Son of Sam (David Berkowitz), who acted on delusions.
15. Brain studies of murderers show differences in the amygdala, which regulates fear and aggression.
16. During the COVID‑19 pandemic, homicide increased about 30% year‑on‑year, the largest increase ever recorded.
17. Other crime types decreased during the pandemic.
18. Contributing factors to the homicide rise included financial strain, stress, and de‑policing after the George Floyd murder.
19. The United States homicide rate is 4.38 per 100,000 residents.
20. Most similarly developed countries (Europe, Canada, Australia) have homicide rates under 1 per 100,000.
21. Some Latin American countries (Honduras, Mexico, Jamaica) have higher homicide rates than the United States.
22. Psychopathy can be present without obvious outward signs; high rates are found in entertainment, law enforcement, and politics.
23. A possible giveaway of psychopathy is difficulty reading others’ emotions and mimicking emotions without feeling them.
24. The term “sociopath” is largely outdated; the criminology field prefers “psychopathy” as a clinically definable and testable construct.
25. Since the early 1990s, the gun murder rate has decreased while gun ownership has increased; there are now more guns than people in the United States.
26. About 120 Americans are killed by guns each day (including homicides, suicides, accidents, and police shootings).
27. Approximately half a million people go missing in the United States each year, down from about a million per year in the 1990s.
28. Roughly 90% of missing persons are young people running away from home, leaving about 50,000 missing and unaccounted for annually.
29. 98% of mass shooters are male.
30. About 91‑92% of mass shooters are students at the school they attack.
31. School shooters often come from homes with violence and abuse, study other perpetrators, feel a connection to them, and target their own school due to grievance.
32. School shootings are planned as final acts; perpetrators seek notoriety and want to be known for the act.
33. Alex Murdoch was convicted of killing his wife and child; he may be linked to other murders.
34. In small communities, independent investigations can be difficult when a suspect has high status or power.
35. Criminology TV programs produce a “CSI effect” on jurors (expecting forensic evidence), but no similar effect has been found for criminals learning from shows.
36. America’s most prolific serial killer is Samuel Little, who confessed to killing over 90 people.
37. Samuel Little’s victims were primarily sex workers, drug‑addicted women, and homeless women; his method was strangling.
38. DNA evidence linked Samuel Little to many of his crimes, leading to his confessions.
39. Certain occupations appear over‑represented among serial killers, including mechanics, machinists, truck drivers, and police officers.
40. Female serial killers are often found in caring professions; a study of 16 nurses who committed serial murder found poisoning as a common method and long periods of nondetection due to their profession.
41. A British nurse was sentenced for killing seven newborn babies.
42. American nurse Kristen Gilbert was convicted of murdering four patients under her care.
43. Serial killers typically begin killing in their mid‑to‑late 20s, later than the onset of other violent behaviors.
44. The Zodiac Killer committed at least five murders in Northern California in the 1960s, sent letters and ciphers to newspapers, and has never been conclusively identified.
45. One of the Zodiac Killer’s ciphers was solved recently, about 60 years after the crimes.
46. Serial killers in prison often receive many marriage proposals from women attracted to their dangerousness.
47. Family annihilation (a man killing his wife, children, then himself) occurs about 10‑20 times per year in the United States.
48. Family annihilators are typically men in their 40s‑50s with histories of domestic violence and suicidality.
49. Jeffrey Dahmer ate victims’ bodies; proposed motives include dominance/control or loneliness/connection.
50. Advances in technology (especially DNA) and behavioral changes (less hitchhiking) have contributed to the decline of serial killing since its peak in the 1970s‑1990s.
51. Most missing hiker cases result from accidents or falls; a small number involve serial killers.
52. Gabby Petito was killed by her fiancé while hiking, illustrating a lack of guardianship on trails.
53. Routine activity theory states that crime requires a motivated offender, a suitable target, and a lack of capable guardianship; hiking exemplifies low guardianship.