Skip to main content

The Globe and Mail

Google ads discriminate against African-Americans: study

Staff of Google company work in front of a illuminated sign at the industrial fair Hannover Messe in Hanover, Germany, Tuesday, April 17, 2007, when Google presented the online promotion program AdWords.


The lucrative Google program that pairs ads with each search-engine query discriminates when it handles given name associated with African-Americans, says a recent Harvard University study.

Searching on the news site, which hosts Google-provided ads, black-identified first names were 25 per cent more likely to yield an add offering the services of Instant Checkmate, a company which offers criminal record checks, the Harvard research found.

"There is less than a 0.1 per cent probability that these data can be explained by chance... There is discrimination in delivery of these ads," the paper concludes.

Story continues below advertisement

The research stemmed from the personal experience of the author, a black woman with no criminal record.

When Harvard computer scientist Latanya Sweeney types her name into Google, the search result yields an Instant Checkmate ad, titled "Latanya Sweeney Arrested?"

Searching for "Kristen Lindquist" or "Jill Foley," however, produced more neutral results – for example, a wedding registry ad, or an Instant Checkmate ad that didn't suggest the subject had a criminal history and just said: "Located… information found on Jill Foley."

(In fact, women with names like Kristen Lindquist or Jill Foley have criminal histories, the study found.)

To place an online ad, clients provide Google with search criteria and ad text that is to be delivered if that search criteria is used.

Google's ad programs – AdWords, which allows advertisers to specify search criteria, and AdSense, which delivers the ads – generate nearly $10-billion in revenue each year.

Dr. Sweeney's paper acknowledges that it "raises more questions than it answers."

Story continues below advertisement

The paper says the ad-placement bias could come from a combination of factors.

Perhaps, the paper says, the advertiser provided search templates that were disproportionately skewed towards black names.

Another possibility was that Google stored previously placed ads in a fast-access memory cache for quicker retrieval, therefore skewing future placements.

Still another scenario was that Google's software might have an algorithm that records which ad texts drew more views, then would adjust its offerings to maximize ad clicks.

In other words, society at large could be to blame, for clicking more often on ads suggesting that blacks have an arrest record.

In a statement emailed to The Globe and Mail, Google said that Google Adwords, the program which allow advertisers to specify search criteria, "does not conduct any racial profiling."

Story continues below advertisement

"It is up to individual advertisers to decide which keywords they want to choose to trigger their ads," Google said, adding that it has policies forbidding the promotion of discriminatory content.

Clouding the issue further, Dr. Sweeney says Instant Checkmate's founders told her that they give the same ad text for Google for groups of last names, not first names.

"Is there a combinatorial effect? This paper is a start and more research is needed," the paper says.

For her study, Dr. Sweeney expanded that observation by studying what ads came up when searching from a database of 2,184 first names. The first names came from previous research that looked at the way African-Americans began in the 1970s to give their children distinctive given names.

After each name search, the resulting ads were recorded and the browser's cache and cookies were cleared before proceeding with the next name.

Dr. Sweeney is the director of Harvard's Data Privacy Lab. Ironically, research for her paper was partly funded by Google.

Report an error Licensing Options
About the Author
National reporter

Tu Thanh Ha is based in Toronto and writes frequently about judicial, political and security issues. He spent 12 years as a correspondent for the Globe and Mail in Montreal, reporting on Quebec politics, organized crime, terror suspects, space flights and native issues. More


The Globe invites you to share your views. Please stay on topic and be respectful to everyone. For more information on our commenting policies and how our community-based moderation works, please read our Community Guidelines and our Terms and Conditions.

We’ve made some technical updates to our commenting software. If you are experiencing any issues posting comments, simply log out and log back in.

Discussion loading… ✨

Combined Shape Created with Sketch.

Combined Shape Created with Sketch.

Thank you!

You are now subscribed to the newsletter at

You can unsubscribe from this newsletter or Globe promotions at any time by clicking the link at the bottom of the newsletter, or by emailing us at