Jacob Kang-Brown

graphic pie chart showing the scope of immigrant incarceration in the US. While ICE detention data recorded 57,200 people on average in June 2025, a broader count of people detained shows the overall crimmigration system is 45% larger, at around 83,400 people.

So many important takeaways in this new report about jails and mass deportation from @prisonpolicy.org @jkangbrown.bsky.social 1) the scope of immigrants incarcerated *for immigration* is much higher than what is reported by ICE www.prisonpolicy.org/reports/jail...

Hiding in Plain Sight: How local jails obscure and facilitate mass deportation under Trump

🚨NEW: Local jails & police departments are playing a key role in Trump’s mass arrest & deportation agenda

The actual scope of this collaboration – and the true scale of immigrant arrests and detentions – has not been publicly available, until now 🧵

Hiding in Plain Sight: How local jails obscure and facilitate mass deportation under Trump

New report on deportation and local jails from @jkangbrown.bsky.social and @prisonpolicy.org

www.prisonpolicy.org/reports/jail...

Vera is hiring a graduate student intern for the summer on my team. We’re researching incarceration and inequality, and looking for ~20 hours a week, in Brooklyn. Please share with graduate students you know who might be interested. boards.greenhouse.io/verainstitut...

Screenshot of page 19 on the report: https://vera-institute.files.svdcdn.com/production/downloads/publications/People-in-Jail-and-Prison-in-2024-Report.pdf#page=19

The report covers recent jail and prison construction, highlighting how fiscal and monetary policy context has shaped funding approaches and the $62 billion in local jail construction that has expanded jail capacity nearly 40 percent since early 2000s.

Explore the data here: trends.vera.org

People in Jail and Prison in 2024 To provide the public with timely information on how incarceration is changing in the United States, Vera collected quarterly data from jails and prisons from mid-year 2019 through spring 2024. Vera a...

New report here: www.vera.org/publications...

New analysis from our team at the Vera Institute shows urban jail incarceration rates continue to decline. By spring 2024, urban jail rates were 30 percent under the national rate while rural county jails are 71 percent higher than the national rate (per 100k working age adults).

Hi Jeff! I think it’s worth getting something like that out, this thread is just a first step in the process.

GitHub - jkangbrown/when_police_replication: Replication and re-analysis repository for Nix et al. "When police pull back: Neighborhood-level effects of de-policing on violent and property crime, a re... Replication and re-analysis repository for Nix et al. "When police pull back: Neighborhood-level effects of de-policing on violent and property crime, a research note." For more informati...

I first discovered the problem in April 2024, and contacted the journal on April 12, and the authors on April 16. In order to ensure transparency for replication and reanalysis, I placed all the original code as well as my edits into a Github repository. github.com/jkangbrown/w...

Scholars have long shown community structural characteristics like disadvantage are related to police-recorded stats on crime. To find “no impact at all” should have been a red flag to a careful reader.

A clue to this merge problem might have been noticed earlier. The disadvantage variable in the authors models had very small coefficients that were not significantly different from zero.

In order to replicate the article’s results, I looked at the authors’ published materials, downloaded their data and code for replication from the Open Science Framework, and made necessary customizations to run the analysis.

If you fix the data merges and then use the rest of the authors’ analysis code, one arrives at opposite results. Reduced police pedestrian and traffic stops have no impact on violent or property crime. And reduced drug and public order arrests also have no impact.

While Lincoln Park’s actual poverty rate is 38 percent with a median household income of $37,166, it is matched to Lowry Field’s 8 percent poverty rate and household income of $102,313.

As one example, the Denver neighborhood Lincoln Park has correct police stop, arrest, and traffic accident information, but it is matched to Lowry Field’s population, housing, and demographic data.

Map of Denver's neighborhoods with 52 out of 78 colored red to indicate improper data matching.

The findings in the published paper, however, are completely untrue, and can only be replicated using an improperly merged dataset. The findings are an artifact of failed data management.

In their article, the authors find reduced police stops of pedestrians and vehicles are associated with more violent crime, and reduced drug-related arrests are associated with more property crime.

When police pull back: Neighborhood‐level effects of de‐policing on violent and property crime, a research note Many U.S. cities witnessed both de-policing and increased crime in 2020, yet whether the former contributed to the latter remains unclear. Indeed, much of what is known about the effects of proactive....

A recent article in Criminology indicates that it found evidence that “de-policing” increased violent and property crime in Denver neighborhoods. However, as I will explain, the so-called evidence for this claim is nonexistent. onlinelibrary.wiley.com/doi/10.1111/...

Some academics tried to make more sophisticated arguments about Black Lives Matter protests and used the term “de-policing” to refer to the reductions in aggressive policing tactics in the wake of calls for accountability.

During 2020, some carceral advocates blamed increased violence on Black Lives Matter demonstrators. These arguments were all over the media landscape.

Criminology – the flagship journal in the discipline – recently published an article with completely erroneous results about the impact of reduced policing on crime. This has major implications for public budgets and public policy.

A False Choice How one Texas county is using women’s incarceration to justify a new jail

Texas suburbs are building a lot of new jails--my colleagues and I wrote about one. Just published with the Vera Institute: www.vera.org/in-our-backy...