Crimes known to police are not the majority of crimes

More serious crimes are more reliably reported; homicides, robberies, serious thefts (insurance)

Participation is not mandatory, so some places no covered

UCR reporting sometimes inconsistent--better to compare within locality than between them

NIBRS--new system--is emerging but doesn't have full coverage

NCVS leverages expertise of census bureau with stratified multistage cluster sample.

Interviews entire household every 6 months over three year period.

Problem: Domestic violence

Disadvantage: Sample means smaller area estimates not representative or reliable; insufficient power

This is UCR--usually very accurate for these crime types

The crime peak was somewhat highly concentrated in city centers

Heavily weighted toward gun violence related to drug sales and gangs; racially disparate

Homicide rates now look like early 1960s--a bit higher than 1950s which were an all-time low while stats tracked

UCR does not capture these crime types accurately, so this is NCVS

Thefts higher than 1960s but otherwise similar--we're at nearly an all-time low

Decomposition is a fancy word for separating out different sources of variation

In this simple case, every city has a different average level of crime, and every point has random variation

But once you remove the shared change they all experienced, all that remains is that different base and random variation

Be skeptical of politicians taking credit for crime declines when the trends are similar elsewhere--and even if they aren't, they probably didn't do it either.

Slightly misleading as there was another trough at the start here--but stats not well kept then.

Prohibition kept rates up high until 1930s

War and post-war period were unique with full employment, massive economic expansion

Crime in general peaks around 16-21.

This is a stable empirical reality pretty much everywhere and throughout time

All theories of crime must address this to be relevant

The average age of victims is about 32, of offenders about 28

About 50% of homicide victims know their offender; drastically higher for children

This is Office of Juvenile Justice and Delinquency Prevention data

Arrests not same as participation; majority of crimes, especially minor, go unnoticed.

May represent changes in policy as well as underlying rates.

Vast majority of murders are committed by men

Most victims are also male

Nearly all homicides of women are done by men, however

Homicide offending and victimization is highly concentrated in young black male population

This is aprticularly the case in the early 1990s

We'll get more of a handle on this later when we read Divergent Social Worlds

The vast majority of violence occurs between people who are acquainted

People typically know others like themselves

Violence is more concentrated in more segregated areas and among more segregated people (i.e. poorer)

Crime is highly concentrated among males, and incarceration even more so--approximately tenfold difference.

In large part because involvement in violence is even more concentrated among men than crime in general.

We have the highest officially reported incarceration rate in the world

It is unlikely that all countries accurately report incarceration statistics, so take them with a grain of salt

This plot shows incarceration rates by time of crime since 1980.

This looks pretty bad, but keep in mind it lumps together all drug crimes while disaggregating violence and not including theft, the most common property crime--rates increased for everything.

Increase in incarceration was larger for black and hispanic populations, though whites did see a more than doubling.

That's comparable proportional increase for whites and hispanics, but much higher for black.

Not illustrated, but on a sidenote, people in prison typically cannot vote--but they get counted for allocating representation.

If 50% of the people in your district are incarcerated, each non-incarcerated person effectively counts as two votes.

Having a large prison in your area can give you a big boost in political power. This results in a shift of political power from urban black and Latino areas (where people get arrested) to rural white areas (where prisons are). There's movements to get that pop reallocated to the pre-incarceration districts of prisoners.

Despite war on drugs, current prison population is not dominated by drug offenders

Drug offenses often have shorter sentences--more turnover than for violent crimes

Increase in incarcerated population due mainly to general increase in sentences across the board

People are staying in jail and prison longer than they used to.

Added this to satisfy some curiosity many probably have. This is an area chart that shows the amount of different types of calls Philly police responded to in 2019--note this is calls not time spent on calls. More serious calls get more time.

Most calls are noncriminal incidents and false alarms--but note they're also largely not social service calls.

Rather, most calls deal with public order issues.

But for the rest, there is about an equal number of calls for serious crimes and calls that might be classified as medical or social services--though in many cases the police are responding as escort for medical or social service providers.

If you looked at time spent, rather than raw calls, the more serious events would greatly increase in size.

Back to arrests for drugs

Massive increase in arrests mainly seen for black individuals

Another thing to note is most policing is reactive and there's good evidence people are more likely to call the police on black and Hispanic people. Police are also disproportionately deployed to minority areas--in particular to target drug markets. You don't need any individual officer bias to generate these outcomes--the issue is structural.

Substance use tends to be somewhat higher for whites than blacks

Highest groups typically AINA; Hispanic lower than black, Asian lowest

Pattern of arrest and incarceration follows concentration of police attention more than patterns in use or sales

One major reason is most white use and sales occur in private premises where it goes unseen; poorer folk hustle and use on the street

Framers of constitution were suspicious of federal government; state-regulated militias were thought to protect from federal government

Complex though: Conception is that one cannot ban arms because citizens make up the militia; guns typically owned by individuals

Conception of individual right to bear arms--as opposed to collective state-level--is basically nonexistent until 1960s and was not legally mainstream until 2000s, even among conservative justices.

Case established precedent for individual right to gun ownership independent of militia and including for self-defense.

Issue more or less settled for now barring a constitutional amendment--common law precedent has established an individual right.

Top 10 gun ownership countries over 10 million pop.

US civilians own just shy of 400 million firearms, which is estimated to be about 46% of all guns in the world

That's about three times the firearms held by all militaries in the world combined (133 million).

Gun ownership in US (vs Europe) is more heavily weighted toward handguns; direct comparisons of gun counts are misleading as handguns are generally the issue--most homicides involve handguns.

Overall gun death rates are correlated with gun ownership by state.

Gun homicide rates exhibit a weaker correlation because of the rural vs. urban issue--will get to that

The number of people owning guns is dropping over time, but the number of guns owned is increasing.

Gun owners tend to be older white males in rural areas

Urban gun ownership is uncommon

The highest risk group for firearm violence is young black males who have low rates of gun ownership in general

Can't disaggregate above by police, but vast majority of police homicides are shootings.

Legality of firearms involved in crime is not well recorded

What work has been done suggests majority are obtained via direct theft, sale of stolen weapons, or unrecorded transfers.

This means most homicides are attached to guns--but those guns aren't acquired through legitimate channels

At the initial stage, however, they were purchased legally, so there is a lot of concern about minimizing thefts or transfers and tracing weapon origins.

These are assault deaths compared to similar OECD countries.

Most assault deaths are firearms in US. Lower firearm death rates elsewhere.

Not a good look

Actual rates of assault are not this out of proportion--we have roughly similar assault rates to rest of OECD.

The issue here is more effective weapons in course of assaults--primarily handguns.

Bringing in some excluded OECD countries--Mexico and Estonia--it makes US look a little better

Until you consider Mexico has a continuous drug war going on. Recent spike back up was beginning of Calderon's militaristic approach to cartels.

Estonia had serious issues with drug crime, organized crime, and alcohol abuse after gaining independence and shifting to market economy. It now has a lower homicide rate than the US.

Gun homicide rates--not just counts--are much higher in urban areas than rural

Gun homicides are concentrated in small number of cities, small areas within those cities

Differences in violence often don't map to other crimes: St. Louis only about 20% more property crime than Seattle

Gun ownership is a rural thing, but gun homicides are an urban thing

Relationship is complex.

This plot compares firearm homicide rates in US cities to comparable countries

Note that within the comparison countries, they have individual cities with similar concentrations

Mass shootings look very different from other homicides

If you're expecting conflict, handguns can be carried all the time

If you want to inflict maximum harm, long guns are universally superior

This is why mass shootings and conventional homicide are totally different things; can't address the same way; same with domestic violence

Ownership only really correlated with domestic violence homicides (and suicides)

No one is shipping guns straight to criminals

Original source of guns is always some legitimate sale

Pathway is through theft or transfers

Gun ownership externality: Legal ownership enables illegal gun acquisition via theft.

What is unique about guns isn't that people can steal the item and use it illegally, but rather the consequences of that illegal use are unusually severe compared to other things that might be stolen--like drugs.

Liberty doctrine of US makes it hard to legally restrict ownership due to this externality, even though the majority of homicides in US can be attributed to it. People do not like idea of regulating people obeying law because of actions of people already breaking law.

Firearm owners and lobby are a large and powerful voting block, many of whom share a moral anti-regulation stance.