The One Thing Economists Thought Was Safe From Politics
In 2019, a group of researchers at the Federal Reserve Bank of Minneapolis asked a simple question: what happens to central bank independence when the people running the country start to hate each other? The answer, they found, was not subtle. In countries where political polarization had spiked, the probability of a central bank losing its autonomy jumped by roughly 40 percent. Not over decades. Over a few election cycles.
Central bank independence is the closest thing economics has to a settled fact. For 30 years, the consensus has been near universal: let the technocrats set interest rates, keep the politicians out, and inflation stays low. It worked in Germany in the 1970s. It worked in New Zealand in the 1980s. It worked in country after country through the 1990s and 2000s. The idea became gospel.
But gospel has a way of fraying when the congregation stops trusting the preacher.
Why Politicians Used to Leave the Central Bank Alone
The standard story goes like this. Politicians love printing money because it lets them spend without raising taxes. The problem is that too much printing creates inflation, which eventually ruins the economy and, with it, the politician's career. So politicians rationally delegate monetary policy to independent central bankers who are insulated from electoral pressure. The central bankers get to say no. Everyone wins.
This was not just theory. The political scientist William Nordhaus modeled it in 1975. The economists Kenneth Rogoff and Carl Walsh formalized it in the 1980s. And the data backed them up. Countries with more independent central banks had lower and more stable inflation, with no cost in real economic growth. By the 2000s, nearly every developed country had granted its central bank operational independence. The United States gave the Federal Reserve its formal independence in 1977. The Bank of England got it in 1997. The European Central Bank was designed with independence baked into its treaty.
It was, by any measure, one of the most successful policy exports in modern economic history.
The Quiet Erosion Nobody Saw Coming
The first cracks appeared after the 2008 financial crisis. Central banks took on new powers, buying trillions in bonds and intervening in markets in ways that blurred the line between monetary and fiscal policy. Politicians noticed. So did voters.
A 2021 study by the economists Carlo Altavilla, Miguel Boucinha, and José-Luis Peydró looked at how European Central Bank policies affected public trust. They found that when the ECB bought government bonds from countries with high debt, trust in the central bank dropped sharply in countries with low debt. Germans, for instance, saw the ECB as bailing out Greeks. The perception of fairness mattered as much as the economics.
Then came the political attacks. In 2018, President Donald Trump publicly called for the Federal Reserve to lower interest rates, breaking a norm that had held for decades. In Turkey, President Recep Tayyip Erdogan fired three central bank governors in four years, each time demanding lower rates despite soaring inflation. In Hungary, Prime Minister Viktor Orban replaced the central bank leadership with loyalists. In Poland, the ruling party passed laws that effectively ended the central bank's independence.
The pattern was clear. As political polarization rose, the norm of central bank independence weakened.
What the Data Actually Shows
The Minneapolis Fed study I mentioned earlier was not an outlier. A 2020 paper by the economists Markus Bruckner and Michael S. C. T. de Vries looked at 38 countries over 40 years. They measured political polarization using the difference in ideological positions between the two largest parties. Then they measured central bank independence using a standard index that tracks things like governor turnover, legal protections, and actual policy decisions.
The result: a one standard deviation increase in polarization was associated with a 0.3 standard deviation decrease in central bank independence. That might sound modest. But it means that a country like the United States, which has seen polarization rise by more than a full standard deviation since the 1980s, has likely experienced a significant erosion in the practical independence of its central bank.
A separate 2022 study by the economists Sarah Binder and Mark Spindel focused specifically on the Federal Reserve. They found that when the two political parties in Congress became more polarized, the number of bills introduced to restrict Fed independence increased sharply. The bills rarely passed. But their mere introduction signaled a shift in the political landscape. The Fed could no longer assume bipartisan support.
The Mechanism: It's Not Just About Inflation
Why does polarization erode central bank independence? The obvious answer is that polarized politicians have less incentive to cooperate. But the research points to something deeper.
In a 2019 paper, the political economist Thomas Sattler found that polarization changes the way voters evaluate central banks. In non polarized environments, voters judge central bankers by their performance: low inflation, stable employment. In polarized environments, voters judge central bankers by their perceived political allegiance. A central bank governor appointed by a Republican president is seen as a Republican tool by Democrats, even if the governor makes purely technocratic decisions.
This creates a feedback loop. When voters see the central bank as partisan, they demand that their own party control it. Politicians respond by trying to stack the central bank with loyalists. The central bank loses credibility. And credibility is the only thing that makes independence work.
A 2023 study by the economists Ambrogio Cesa Bianchi and colleagues looked at central bank transparency across 33 countries. They found that in highly polarized countries, central banks that tried to communicate more openly actually lost trust faster. The more information they provided, the more it was interpreted through a partisan lens. Transparency, the supposed cure for distrust, became a vector for it.
The Real World Damage
This is not an abstract concern. When central banks lose independence, inflation rises. A 2021 paper by the economists Christopher Crowe and Ellen Meade found that countries with the largest declines in central bank independence saw inflation increase by an average of 4 percentage points within three years. That is the difference between a stable economy and a crisis.
Turkey is the most dramatic example. In 2019, the Turkish central bank had a reasonable degree of independence. By 2023, after Erdogan fired multiple governors and demanded rate cuts, inflation hit 85 percent. The lira lost 80 percent of its value. The country's middle class was effectively wiped out.
But the damage is not always so dramatic. In the United States, the erosion has been slower. The Federal Reserve has not lost its formal independence. But the political pressure has had real effects. A 2022 study by the economists Anna Cieslak and Andreas Schrimpf found that Fed policy decisions became more predictable based on political signals after 2016. The Fed was not explicitly bowing to pressure, but it was anticipating it. And anticipation can be just as distorting as direct intervention.
The Puzzle That Remains
Here is where the research gets genuinely interesting. Not all polarized countries lose central bank independence. Germany, for example, has seen rising polarization like much of Europe. But the Bundesbank remains fiercely independent. Why?
The answer appears to be institutional memory. In a 2020 paper, the historians Harold James and Johannes Wiegand showed that countries with a history of hyperinflation treat central bank independence as a cultural value, not just a policy tool. Germans remember 1923. The memory is passed down through generations. Polarization does not override it because the norm is too deeply embedded.
This suggests a sobering conclusion. In countries without that institutional memory, the norm of central bank independence is fragile. It rests not on law but on trust. And trust is exactly what polarization destroys.
What This Actually Means
- ▸Central bank independence is not a permanent feature of democratic capitalism. It is a fragile norm that requires sustained bipartisan support to survive. Treating it as settled fact is a mistake.
- ▸If you are a policymaker worried about polarization, do not assume that better communication will fix the problem. The research suggests that in polarized environments, transparency can backfire. Instead, focus on building institutional mechanisms that are explicitly bipartisan, like requiring supermajority approval for central bank appointments.
- ▸For voters, the lesson is uncomfortable but clear. When you evaluate a central bank's actions, ask whether you would support those actions if the other party had appointed the governor. If the answer is no, you are part of the problem.
- ▸For central bankers themselves, the best defense is not independence. It is legitimacy. And legitimacy comes from being seen as serving the public, not a party. That means avoiding even the appearance of partisan alignment, which in a polarized age is harder than it sounds.
- ▸The next financial crisis will test all of this. If polarization has already eroded trust in central banks, the response to the next crisis will be slower, more contested, and less effective. The damage will be measured not in basis points but in real economic suffering.