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The TGA is Worse than the FDA, and the Australian Lockdown

I have been highly critical of the FDA but in Australia the FDA is almost a model to be emulated. Steven Hamilton and Richard Holden do not mince words:

At the end of 2020, as vaccines were rolling out en masse in the Northern Hemisphere, the TGA [Therapeutic Goods Administration, AT] flatly refused to issue the emergency authorisations other regulators did. As a result, the TGA didn’t approve the Pfizer vaccine until January 25, more than six weeks after the US Food and Drug Administration (FDA), itself not exactly the poster child of expeditiousness.

Similarly, the TGA didn’t approve the AstraZeneca vaccine until February 16, almost seven weeks after the UK.

In case you’re wondering “what difference does six weeks make?“, think again. Were our rollout six weeks faster, the current Sydney outbreak would likely never have exploded, saving many lives and livelihoods. In the face of an exponentially spreading virus that has become twice as infectious, six weeks is an eternity. And, indeed, nothing has changed. The TGA approved the Moderna vaccine this week, eight months after the FDA.

It approved looser cold storage requirements for the Pfizer vaccine, which would allow the vaccine to be more widely distributed and reduce wastage, on April 8, six weeks after the FDA. And it approved the Pfizer vaccine for use by 12 to 15-year-olds on July 23, more than 10 weeks after the FDA.

And then there’s the TGA’s staggering decision not to approve in-home rapid tests over reliability concerns despite their widespread approval and use overseas.

Where’s the approval of the mix-and-match vaccine regimen, used to great effect in Canada, where AstraZeneca is combined with Pfizer to expand supply and increase efficacy? Where’s the guidance for those who’ve received two doses of AstraZeneca that they’ll be able to receive a Pfizer booster later?

In the aftermath of the pandemic, when almost all of us should be fully vaccinated,there will be ample opportunity to figure out exactly who is to blame for what.

But the slow, insular, and excessively cautious advice of our medical regulatory complex, which comprehensively failed to grasp the massive consequences of delay and inaction, must be right at the top of that list.

You might be tempted to argued that the TGA can afford to take its time since COVID hasn’t been as bad in Australia as in the United States but that would be to ignore the costs of the Australian lockdown.

Article 13 of the Universal Declaration of Human Rights states that

  1. Everyone has the right to freedom of movement and residence within the borders of each state.
  2. Everyone has the right to leave any country, including his own, and to return to his country.

Australia has now violated each and every clause of this universal human right and seemingly without much debate or objection. It is deeply troubling to see people prevented from leaving or entering their own country and soldiers in the street making sure people do not travel beyond a perimeter surrounding their homes. The costs of lockdown are very high and thus so is any delay in ending these unprecedented infringements on liberty.

My Conversation with Andrew Sullivan

Here is the audio, video, and transcript.  Here is part of the overview:

Andrew joined Tyler to discuss the role of the AIDs epidemic in achieving marriage equality, the difficulty of devoutness in everyday life, why public intellectuals often lack courage, how being a gay man helps him access perspectives he otherwise wouldn’t, how drugs influence his ideas, the reasons why he’s a passionate defender of SATs and IQ tests, what Niall Ferguson and Boris Johnson were like as fellow undergraduates, what Americans get wrong about British politics, why so few people share his admiration for Margaret Thatcher, why Bowie was so special, why Airplane! is his favorite movie, what Oakeshottian conservatism offers us today, whether wokeism has a positive influence globally, why he someday hopes to glower at the sea from in the west of Ireland, and more.

And here is one excerpt:

SULLIVAN: Well, and so you get used to real conversations about people, and you don’t mistake credentials for intelligence. You realize that people outside of the system may be more perceptive about what’s going wrong with it than people buried within it. I honestly find life more interesting the more variety of people you get to know and meet. And that means from all sorts of different ways of life.

The good thing about being gay, I will tell you, is that that happens more often than if you’re straight — because it’s a great equalizer. You are more likely to come across someone who really is from a totally different socioeconomic group than you are through sexual and romantic attraction, and indeed the existence of this subterranean world that is taken from every other particular class and structure, than you would if you just grew up in a straight world where you didn’t have to question these things and where your social life was bound up with your work or with your professional peers.

The idea for me of dating someone in my office would be absolutely bizarre, for example. I can’t believe all these straight people that just look around them and say, “Oh, let’s get married.” Whereas gay people have this immense social system that can throw up anybody from any way of life into your social circle.

Interesting throughout.  And again, here is Andrew’s new book Out on a Limb: Selected Writing, 1989-2021.

Our Regulatory State Isn’t Learning

Outsourced to John Cochrane:

Delta is the fourth wave of covid, and amazingly the US policy response is even more irresolute than the first time around. Our government is like a child, sent next door to get a cup of sugar, who gets as far as the front stoop and then wanders off following a puppy.

The policy response is now focused on the most medically ineffective but most politically symbolic step, mask mandates. An all-night disco in Provincetown turns in to a superspreader event so… we make school kids wear masks in outdoor summer camps? Masks are several decimal places less effective than vaccines, and less effective than “social distance” in the first place.* Go to that all night disco, unvaccinated, but wear a mask? Please.

If we’re going to do NPI (non pharmaceutical interventions), policy other than vaccines, the level of policy and public discussion has tragically regressed since last summer. Last summer, remember, we were all talking about testing. Alex Tabarrok and Paul Romer were superb on how fast tests can reduce the reproduction rate, even with just voluntary isolation following tests. Other countries had competent test and tracing regimes. Have we built that in a year? No. (Are we ready to test and trace the next bug? Double no.)

What happened to the paper-strip tests you could buy for $2.00 at Walgreen’s, get instant results, and maybe decide it’s a bad idea to go to the all night dance party? Interest faded in November. (Last I looked, the sellers and FDA were still insisting on prescriptions and an app sign up, so it cost $50 and insurance “paid for” it.) What happened to detailed local data? Did anyone ever get it through the FDA’s and CDCs thick skulls that even imperfect but cheap and fast tests can be used to slow spread of disease?

…And then we indulge another round of America’s favorite pastime, answers in search of a question. Delta is spreading, so… extend the renter eviction moratorium. People who haven’t paid rent in a year can stay, landlords be damned.

All true. I got dispirited on testing. It’s insane that we don’t have cheap, rapid testing and good ventilation ready for a new school year. As I wrote about earlier, even the American Academy of Pediatrics is shouting from the rooftops that the FDA is deadly slow. The eviction moratorium is a sick joke. Just a backhanded way to redistribute wealth without a shred of justice or reason. Disgusting.

Here’s one more bit (but read the whole thing there is more.)

To learn from the mistakes, and institutionalize better responses would mean to admit there were mistakes. One would think the grand blame-Trump-for-everything narrative would allow us to do that, but the mistakes are deeply embedded in the bureacracies of the administrative state. Unlike bad admirals in WWII, nobody less than Trump himself has lost their job over incompetent covid response. The institutions have an enormous investment in ratifying that they did the best possible job last time. So, as in so many things (financial bailouts!) we institutionalize last time’s mistakes to keep those who made them in power in power — which means we do not learn from mistakes.

The incentives for Mexican hotel Covid testing

Yes you need a negative result on the test to return to the United States, but you never know the sensitivity of the test you are taking.  It should be from an “approved provider,” but what does that mean?  No authority from the United States can readily verify how good the test is.

Let us say you are a hotel owner, which kind of testing service do you wish to commission to send around to your rooms to test your American guests?  A highly sensitive test that will yield periodic false positives, or a not very sensitive test that won’t generate false positives and might even result in some false negatives?  And say some of your guests truly will be Covid-positive — do you wish to keep them in their rooms for another week or two, with all the attendant risks, or do you wish to send them along their way?

You don’t even have to imagine that the hotel owners are entirely cynical.  They themselves can’t judge the accuracy of the tests, so a service that yielded a fair number of Covid positives could be seen as “they make too many mistakes and won’t let our guests leave, we don’t want them.”  If the Delta variant is outracing publicity about the Delta variant, as was the case for a while in Tulum, such a hotelier reaction might be all the more likely.

I did in fact test negative.  And the testers were very nice to me.

Is Haiti Governable Right Now? (at all)

More generally, might there be some countries that simply are not viable nation-states any more, no matter what we do?  That is the topic of my latest Bloomberg column, here is one excerpt:

In other words, at the moment there doesn’t seem to be any way to govern Haiti. One problem is that foreign flows of money, whether from the drug trade or from Venezuelan foreign aid, have overwhelmed the domestic incentives to play by the rules. Haiti’s political institutions are mostly consumed by bribes and rents, with no stable center. The news, so to speak, is that such problems do not always have solutions. At all.

It is fine to suggest that Haiti invest in building up its political institutions — but those institutions have been unraveling for decades. I was a frequent visitor to the country in the 1990s, and although the poverty was severe, it was possible to travel with only a modest risk of encountering trouble. Government was largely ineffective, but it did exist.

These days the risk of kidnapping is so high that a visit is unthinkable.


The buildup and rise of nation-states has become so ordinary that the opposite possibility is now neglected: their enduring collapse. It’s not history running in reverse. It’s that modernity has created new forces and incentives — drug money, kidnapping ransoms, payments from foreign powers, and so on — that can be stronger and more alluring than the usual reasons for supporting an internal national political order. If the rest of the world gets rich more quickly than you do, it might have the resources to effectively neutralize your incentives for peace and good government.

So where else might the political order soon unravel? In parts of Afghanistan, external forces (Pakistan, China, Russia, the U.S.) have so much at stake that the conditions there may never settle down. Other risks might be found in small, not yet fully orderly nations such as Guyana, Equatorial Guinea, and Eswatini (formerly Swaziland). El Salvador and Nicaragua seem to be consolidating their political orders, but at the cost of losing fair democratic political competition. The nation-state as we know it might not survive in every part of Nigeria, where the recent surge in kidnappings is striking.

In the Baltics and Taiwan, dangers from larger, aggressive neighbors lurk. In spite of generally good governance in these places, the pressures from outside powers might be too much to bear, reflecting broadly similar destabilizing mechanisms — namely, that the internal rewards for coordinating support for a status quo might not be high enough.


Alternative Dosing

Close-up medical syringe with a vaccine.

Alternative dosing is finally getting some attention. This story in Nature recounts some of the recent arguments and evidence:

Two jabs that each contained only one-quarter of the standard dose of the Moderna COVID vaccine gave rise to long-lasting protective antibodies and virus-fighting T cells, according to tests in nearly three dozen people1. The results hint at the possibility of administering fractional doses to stretch limited vaccine supplies and accelerate the global immunization effort.

Since 2016, such a dose-reduction strategy has successfully vaccinated millions of people in Africa and South America against yellow fever2. But no similar approach has been tried in response to COVID-19, despite vaccine shortages in much of the global south.

“There’s a huge status quo bias, and it’s killing people,” says Alex Tabarrok, an economist at George Mason University in Fairfax, Virginia. “Had we done this starting in January, we could have vaccinated tens, perhaps hundreds, of millions more people.”

…Sarah Cobey, an infectious-disease researcher at the University of Chicago in Illinois and a co-author of a 5 July Nature Medicine commentary supporting dose ‘fractionation’, disagrees about the need for time-consuming data collection.

“We shouldn’t wait that long,” she says. “People are dying, and we have historical precedent for making very well-reasoned guesses that we think are going to save lives.”

…According to a modelling study published by Tabarrok and other economists, such an approach would reduce infections and COVID-linked deaths more than current policies.

Addendum: The reason for doing the modeling study is precisely to take into account variants like Delta. Our modeling suggests that even with efficacy significantly lower than that suggested by Figure 1 in our paper, alternative doses of more effective vaccines would still provide significant reductions in mortality, even when new variants dominate. The benefits derive from vaccinating more quickly.

Abolishing tenure is the least of my proposals

In my latest Bloomberg column I attempt to design an ideal university from scratch.  The point is not that all schools should be this way, rather this is the experiment I would like to see at the margin:

I would start with what I expect students to know. They should be able to write very well, have  a basic understanding of economics and public policy, and a decent working knowledge of statistical reasoning. I would give a degree to students who demonstrated “B-grade” competence in all of these areas; what now goes for passing C-minus work wouldn’t cut it.

Most important, the people who write and grade the students’ tests would not be their instructors. So students would have to acquire a genuine general knowledge base, not just memorize what is supposed to be on the exam.

Next, each student would have the equivalent of a GitHub certification page. If you learned three programming languages, for example, or won a prize in a science fair, that would go on your page as a credential. But it would not count as a credit toward graduation. Some students could finish their degrees in a year or two even if their pages were not adorned with many accomplishments, while others might fill their pages but get no degree.

My imaginary school would not have many assistant deans, student affairs staff or sports teams. The focus would be on paying more money to the better instructors.


Instructors would not have tenure, but would have to compete for students — by offering them classes and services that would help them graduate and improve the quality of their certification pages. Teachers would be compensated on the basis of how many students they could attract, in a manner suggested long ago by Adam Smith, who himself lived under such a system in 18th-century Scotland.

The very best instructors could earn $300,000 to $400,000 a year…

The school would hire online instructors too, many of them from poorer countries and working at lower wages. So you might take French from a tutor in Senegal, or have a high school teacher from Tamil Nadu read your essays and offer writing tips. I am a big believer in face-to-face instruction, but in my school it would have to compete with online instruction. For this reason, I think my school would have a much more diverse faculty and instructional base than any other institution of higher education. None of the instructors would be required to have any undergraduate or advanced degrees.

The goal is to introduce competition across as many different margins as possible.  There would be an “all on-line” option as well, offered to anyone in the world, though of course the on-line degree might be worth less as judged in the market place.

One issue I did not have time to get into is how the school would “shadow price” its different services to students.  Access to different services has to be priced somehow, so should the school hand out total vouchers to each student for use within the school?  Should the on-line and also face-to-face classes be priced at marginal cost (plus mark-up)?  Or do positive externalities from class cohesion mean that the face-to-face classes should be priced at some additional discount?  To what extent should factors other than this shadow price system be used to allocate access to classes?

The Premonition

In The Premonition Michael Lewis brings his cast of heroes together like the assembling of the Avengers. In the role of Captain America is Charity Dean, the CA public health officer who is always under-estimated because she is slight and attractive, until she cracks open the ribcage of a cadaver that the men are afraid to touch. Then there is Carter Mecher, the redneck epidemiologist who has a gift for assembling numbers into coherent patterns. And Richard Hatchett the southern poet who finds himself at the head of The Coalition for Epidemic Preparedness (CEPI), the world’s most important organization during the pandemic; and Joe DiRisi the brilliant, mad scientist picked by the Chan Zuckerberg Initiative as the person most likely to cure disease…all of them. As you might expect from Michael Lewis, it’s all terribly well done, albeit formulaic and  sometimes over-the-top, e.g.

Charity’s purpose was clear….she was put on earth to fight battles, and wars, against disease. To save lives and perhaps even an entire country. p. 200-201

But Lewis has a bigger problem than over-the-top writing.

The heroes were defeated. Lewis likes to tell stories of brilliant mavericks like Billy Beane and Michael Burry who go against the grain but eventually, against all odds, emerge victorious. But six hundred thousand people are dead in the United States and whatever victory we have won was ugly and slow. Indeed, Lewis assembles his mighty team but then The Premonition trails off as the team is defeated by bureaucracy, indecision, complacency and malaise before they even have a chance to enter the real battle against the virus. It’s telling that none of Lewis’s heroes are even mentioned in Andy Slavitt’s Preventable (about which I will say more in a future post).

To be fair, Lewis’s heroes are fascinating, brilliant people who did some good. As part of the Kremer team I interacted a bit with Richard Hatchett and CEPI. Hatchett headed CEPI and understood the danger of SARS-COV-II before anyone else and with Bill Gates’s support started funding vaccine production and shoring up supply lines before anyone else was off the starting line. CEPI was magnificent and their story has yet to be told in full measure. Had Lewis’s heroes been in charge I have no doubt that many lives could have been saved but, for the most part, the heroes were sidelined. Why and how that happened is the real question but Lewis’s story-telling skills aren’t the right skills to answer that question.

If there is one central villain in The Premonition, it’s the CDC. Lewis acknowledges that his perspective has changed. In The Fifth Risk, the system (the “deep state” used non-pejoratively if you will) is full of wisdom and power but it’s under threat from Trump. In The Premonition, Trump is an after-thought, at best a trigger or aggravating factor. Long before Trump or the pandemic:

Charity had washed her hands of the CDC. “I banned their officers from my investigations,” she said. The CDC did many things. It published learned papers on health crisis, after the fact. It managed, very carefully, public perception of itself. But when the shooting started, it leapt into the nearest hole, while others took fire. “In the end I was like ‘Fuck you’, said Charity. “I was mad they were such pansies. I was mad that the man behind the curtain ended up being so disappointing.” p. 42

As the pandemic starts the CDC fails repeatedly. At the beginning of the pandemic on January 29 the government had started to repatriate Americans from Wuhan bringing some of them to a National Guard base just outside of Omaha. But shockingly the CDC doesn’t test them for the virus.

Never mind that every single one of the fifty-seven Americans in quarantine wanted to be tested: the CDC forbade it. And [James] Lawler [US Naval Commander and national security coordinator on pandemic response] never understood the real reason for the CDC’s objections…Whatever the reasons, fifty-seven Americans spent fourteen days quarantined in Omaha, then left without having any idea of whether they’d been infected, or might still infect others. “There is no way that fifty-seven people from Wuhan were not shedding virus,” said Lawler. p. 176

Many of the people brought home from China are not even quarantined just told to self-quarantine:

…When local health officers…set out to find these possibly infected Americans, and make sure that they were following orders to quarantine, they discovered that the CDC officials who had met them upon arrival had not bothered to take down their home addresses.

…[Charity] posed a rude question to the senior CDC official moved on the call: How can you keep saying that Americans are at low risk from the virus if you aren’t even testing for the virus. She’d been answered with silence, and then the official move on to the next topic. [p.206-207, italics in original]

And all of this is before we get to the CDC’s famously botched test an error which was amplified by the FDA’s forbidding private labs and state governments to develop their own tests. Charity Dean wanted California to ignore the CDC and FDA and, “blow open testing and allow every microbiology lab to develop its own test.” But Dean is ignored and so by as late as February 19, “Zimbabwe could test but California could not because of the CDC. Zimbabwe!” p. 223. The failure of testing in the early weeks was the original sin of the crisis, the key failure that took a containment strategy ala South Korea and Taiwan off the table.

Lewis’s most sustained analysis comes in a few pages near the end of The Premonition where he argues that the CDC became politicized after it lost credibility due to the 1976 Swine Flu episode. In 1976 a novel influenza strain looked like it might be a repeat of 1918. Encouraged by CDC head David Sencer, President Ford launched a mass vaccination campaign that vaccinated 45 million people. The swine flu, however, petered out and the campaign was widely considered a “debacle” and a “fiasco” that illustrated the danger of ceding control to unelected experts instead of the democratic process. The CDC lost authority and under Reagan the director became a political appointee rather than a career civil servant. Thus, rather than being unprecedented, Trump’s politicization of the CDC had deep roots.

Today the 1976 vaccination campaign looks like a competent response to a real risk that failed to materialize, rather than a failure. So what lessons should we take from this? Lewis doesn’t say but my colleague Garett Jones argues for more independent agencies in his excellent book 10% Less Democracy. The problem with the CDC was that after 1976 it was too responsive to political pressures, i.e. too democratic. What are the alternatives?

The Federal Reserve is governed by a seven-member board each of whom is appointed to a single 14- year term, making it rare for a President to be able to appoint a majority of the board. Moreover, since members cannot be reappointed there is less incentive to curry political favor. The Chairperson is appointed by the President to a four-year term and must also be approved by the Senate. These checks and balances make the Federal Reserve a relatively independent agency with the power to reject democratic pressures for inflationary stimulus. Although independent central banks can be a thorn in the side of politicians who want their aid in juicing the economy as elections approach, the evidence is that independent central banks reduce inflation without reducing economic growth. A multi-member governing board with long and overlapping appointments could also make the CDC more independent from democratic politics which is what you want when a once in 100 year pandemic hits and the organization needs to make unpopular decisions before most people see the danger.

Lewis hasn’t lost his ability to write exhilarating prose about heroic oddballs. Page by page, The Premonition is a good read but the heroes in Lewis’s story were overshadowed by politics, bureaucracy and complacency–systems that Lewis’s doesn’t analyze or perhaps quite understand–and as a result, his hero-centric story ends up unsatisfying as story and unedifying as analysis.

USA facts of the day

A survey of almost 200 police departments indicated that retirements were up 45 percent and resignations rose by 18 percent in the year from April 2020 to April 2021 when compared with the previous 12 months, according to the Police Executive Research Forum, a Washington policy institute.

New York City saw 2,600 officers retire in 2020 compared with 1,509 the year before. Resignations in Seattle increased to 123 from 34 and retirements to 96 from 43. Minneapolis, which had 912 uniformed officers in May 2019, is now down to 699. At the same time, many cities are contending with a rise in shootings and homicides.

Asheville was among the hardest hit proportionally, losing upward of 80 officers, more than one third of its 238-strong force.

Here is more from Neil MacFarquhar at the NYT.


After nearly two decades of hardcore drug addiction — after overdoses and rehabs and relapses, homelessness and dead friends and ruined lives — Gerod Buckhalter had one choice left, and he knew it.

He could go on the same way and die young in someone’s home or a parking lot, another casualty in a drug epidemic that has claimed nearly 850,000 people like him.

Or he could let a surgeon cut two nickel-size holes in his skull and plunge metal-tipped electrodes into his brain.

More than 600 days after he underwent the experimental surgery, Buckhalter has not touched drugs again — an outcome so outlandishly successful that neither he nor his doctors dared hope it could happen. He is the only person in the United States to ever have substance use disorder relieved by deep brain stimulation. The procedure has reversed Parkinson’s disease, epilepsy and a few other intractable conditions, but had never been attempted for drug addiction here.

The device, known as a deep brain stimulator, also is recording the electrical activity in Buckhalter’s brain — another innovation that researchers hope will help locate a biomarker for addiction and allow earlier intervention with other people.

Here is the full story.

Can you call this a new service sector job?

Dave Taube has won a computer, a whitewater rafting trip, and several grills. There’s also the kayak, the powder-blue Coors Light onesie, and the Bruce Springsteen tickets. He recently took home $10,000 from Cost Plus World Market in its “World of Joy” sweepstakes. Recently, he found himself in the running for a trip to Antarctica, which would be the thirty-sixth vacation he’s won. His photo and caption, submitted in response to the prompt, “Tell us what you miss about international travel,” got enough votes to make the top 20. Next, the entries went to judging. In Taube’s photo, he’s slung with cameras and wearing safari duds, half-smiling, with a silver goatee. Strategically, he submitted his caption as a poem to make his entry distinct.

Taube, who is 65 and a decades-long resident of the Pacific Northwest, is a sweeper, a term that distinguishes the committed competitor from the casual, onetime entrant. Each day, he enters about 60 sweepstakes—which are random draws—and contests—which are judged.

And this:

Years ago, he entered a contest for “the most boring person in the Pacific Northwest.” He won a whitewater rafting trip, a plane ride, and a certificate for a tandem parachute jump. He sold the certificate.

He is producing…”contest liquidity”?  Publicity?  Contest legitimacy?  In any case he is paid for his labors, albeit in kind.  Here is the full story.

Maradona Plays Minimax

This paper tests the theory of mixed strategy equilibrium using Maradona’s penalty kicks during his lifetime professional career. The results are remarkably consistent with equilibrium play in every respect: (i) Maradona’s scoring probabilities are statistically identical across strategies; (ii) His choices are serially independent. These results show that Maradona’s behavior is consistent with Nash’s predictions, specifically with both implications of von Neumann’s Minimax Theorem.

From Ignacio Palacios-Huerta.

Friday assorted links

1. “Unlike some of these contests, the winner isn’t chosen at random. Instead, “your level of enthusiasm for watching home improvement shows will be a strong factor in the selection process,” according to the contest website.”  Link here.

2. Inequality amongst children.

3. Can bees smell Covid-19?

4. Which incentives for vaccines are most effective for which groups? (NYT)

5. Magnus Carlsen edition: That was then, and this is now (link fixed).

6. The best Ursula Le Guin books?

Why the quality of the police is not higher

According to the Fairfax County Fraternal Order of Police, the average starting salary for a Fairfax County cop is $52,000. The median household income in the county was $124,831 in 2019.


Fairfax County Police Department is down 188 officers, according to Sean Corcoran, president of the Fairfax County Coalition of Police. Officers eligible for retirement are leaving, others are getting out to join higher paying federal agencies like the Capitol Police.

It is thus very difficult to exercise quality control.  Here is the full story.

Vox on BLM

VOX: From 2014 to 2019, Campbell tracked more than 1,600 BLM protests across the country, largely in bigger cities, with nearly 350,000 protesters. His main finding is a 15 to 20 percent reduction in lethal use of force by police officers — roughly 300 fewer police homicides — in census places that saw BLM protests.

Campbell’s research also indicates that these protests correlate with a 10 percent increase in murders in the areas that saw BLM protests. That means from 2014 to 2019, there were somewhere between 1,000 and 6,000 more homicides than would have been expected if places with protests were on the same trend as places that did not have protests. Campbell’s research does not include the effects of last summer’s historic wave of protests because researchers do not yet have all the relevant data.

…One other possible explanation for the increased murder rate is that law enforcement officials are the ones voluntarily reducing their interactions with the community and as a result emboldening criminal activity. One way to observe whether police are reducing their efforts is to see whether the share of property crimes cleared falls over this period. In other words, are police not trying as hard — either because they are demoralized or angry at public scrutiny of their behavior — to solve low-level crimes that are reported to them? Campbell observes a 5.5 percent decline in the share of property crimes cleared, which is consistent with police reducing their efforts immediately following the protests.

Based on this paper. The explanation is consistent with what happened in Baltimore after the Freddie Gray protests and riots, namely arrests went down and murders went up.