Machine Bias

Investigating Algorithmic Injustice

Investigating algorithmic injustice and the formulas that influence our lives.

Facebook (Still) Letting Housing Advertisers Exclude Users by Race

After ProPublica revealed last year that Facebook advertisers could target housing ads to whites only, the company announced it had built a system to spot and reject discriminatory ads. We retested and found major omissions.

Federal Judge Unseals New York Crime Lab’s Software for Analyzing DNA Evidence

We asked the judge to make the source code public after scientists and defense attorneys raised concerns that flaws in its design may have resulted in innocent people going to prison.

Facebook Allowed Questionable Ads in German Election Despite Warnings

CEO Mark Zuckerberg promised to ensure the campaign’s integrity, but the company didn’t take down anti-Green party posts of unknown origin.

German Political Ads Collected From Facebook

During the German parliamentary elections in September, many Germans used ProPublica's Political Ad Collector to identify political advertising in their Facebook news feeds. This database provides a rare window into political ads on Facebook, which are not normally seen by the general public.

Putting Crime Scene DNA Analysis on Trial

We reported on a dispute over the methods used by New York City’s crime lab to analyze complex DNA samples. Now similar concerns are prompting a national study. In this Q&A, a leading expert explains why labs may be making mistakes — and what can be done about it.

ProPublica Seeks Source Code for New York City’s Disputed DNA Software

We’re asking a federal court for the code behind a technique that critics say may have put innocent people in prison.

Facebook Moves to Prevent Advertisers From Targeting Haters

Following our report that advertisers could use Facebook to reach self-identified anti-Semites, the company said it would remove all audience categories based on users’ reports of their interests, education and employment.

Facebook Enabled Advertisers to Reach ‘Jew Haters’

After being contacted by ProPublica, Facebook removed several anti-Semitic ad categories and promised to improve monitoring.

Help Us Monitor Political Ads Online

ProPublica launches a “PAC” to scrutinize campaign ads on Facebook.

Thousands of Criminal Cases in New York Relied on Disputed DNA Testing Techniques

New York City’s crime lab has been a pioneer nationally in analyzing especially difficult DNA samples. But the recent disclosure of the source code for its proprietary software is raising new questions about accuracy.

The Big Problems with Testing Tiny Bits of DNA

New York City’s crime lab has been a pioneer nationally in analyzing especially difficult DNA samples. Now these DNA analysis methods are under the microscope, with scientists questioning their validity.

Have You Experienced Hate Speech on Facebook? We Want To Hear From You.

Help us investigate how Facebook’s censorship policies actually work.

How We Investigated Technology Companies Supporting Hate Sites

We wrote software to find the external domains contacted by popular websites that have been identified as extremist by either the Southern Poverty Law Center or the Anti-Defamation League.

Facebook’s Secret Censorship Rules Protect White Men From Hate Speech But Not Black Children

A trove of internal documents sheds light on the algorithms that Facebook’s censors use to differentiate between hate speech and legitimate political expression.

California to Investigate Racial Discrimination in Auto Insurance Premiums

The state’s insurance department is following up on our findings that eight auto insurers charge more in minority neighborhoods than in other neighborhoods with similar risk.

Lawmakers Seek Stronger Monitoring of Racial Disparities in Car Insurance Premiums

In response to our report that minority neighborhoods pay higher premiums than white areas with the same risk, six members of Congress and two Illinois state senators are pushing for closer scrutiny of insurance practices.

The Car Insurance Industry Attacks Our Story. Here’s Our Response.

An industry representative disputed our findings that many disparities in auto insurance prices between minority and white neighborhoods are wider than differences in risk can explain. His analysis is flawed.

How We Examined Racial Discrimination in Auto Insurance Prices

Chicago Area Disparities in Car Insurance Premiums

Some car insurers charge higher premiums in Chicago’s minority neighborhoods than in predominantly white neighborhoods with similar risk of accidents.

Minority Neighborhoods Pay Higher Car Insurance Premiums Than White Areas With the Same Risk

Our analysis of premiums and payouts in California, Illinois, Texas and Missouri shows that some major insurers charge minority neighborhoods as much as 30 percent more than other areas with similar accident costs.

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