We have experience building tools to document these harms including - browser extensions, data collection panels, and web, mobile and desktop applications. Our work supports journalists and researchers collecting data in the field by capturing incidents as they are happening online. You can think of us as "photojournalists on the streets of algorithm city."

We are hosted by the Center for Information Technology Policy (CITP) at Princeton University.


Sept 12, 2023

Research Associate position in India

This role requires working closely with the India Research Lead, conducting on-the-ground research to support the Lab's work.

Feb 14, 2023

A video helped incite the murder of prominent Bangalore journalist, we investigated its spread on social media

Digital Witness Lab investigated the spread of an edited video of a Gauri Lankesh speech on social media, including YouTube, Facebook, and Twitter. Our goal was to gauge the role the video played in fueling the right-wing Hindu animosity towards her that ultimately led to her murder

Our investigation found that the video had been shared on Facebook, YouTube and Twitter prior to her murder. As of writing, the video has received more than 130 million interactions on Facebook and more than 250,000 views on YouTube. While overall engagement was low on Twitter, there were several instances of the video being shared before her death, including by a Bajrang Dal activist who had been linked to several acts of violence and online hate speech. We also found instances of the video being shared by right-wing activists on Twitter and the BJP Karnataka’s Facebook page before she was murdered, though public interaction with those posts was low. We were unable to investigate the spread on WhatsApp due to the lack of any publicly available tools to measure historical activity.


WhatsApp Watch

A platform for monitoring how election misinformation spreads through WhatsApp groups

We are building the tools necessary to persistently monitor WhatsApp groups for misinformation and other types of harm. WhatsApp Watch will collect data from public groups and analyze metadata to uncover networks of bad actors and other emerging trends. We are launching pilot studies in Brazil and India, where the platform is most widely used. 

If you are a journalist based in these regions, and would like to learn more about WhatsApp Watch, please reach out to us at surya@digitalwitnesslab.org

This project was made possible thanks to a generous Magic Grant from Columbia University’s Brown Institute.

Our Team.

Surya Mattu photograph

Surya Mattu

Lab Lead

Surya is a data journalist and engineer who has worked at The Markup, ProPublica and Gizmodo’s Special Projects Desk. At The Markup he led teams that built Blacklight, a real-time website privacy inspector, and Citizen Browser, a custom application that collected data from the Facebook newsfeeds of over 3000 volunteers. At Propublica he worked on Machine Bias, a series that highlights how algorithmic systems can be biased and discriminate against people in the housing and criminal justice system. Machine Bias was a Pulitzer Prize finalist for Explanatory Journalism

Micha Gorelick photograph

Micha Gorelick

Technology and Reseach Lead

Micha has worked as a machine learning researcher and engineer for The Markup and OCCRP. She was the co-founder of an applied machine learning company, Fast Forward Labs and authored the book “High Performance Python”. She has worked as the lead researcher on a variety of cutting-edge research projects on topics ranging from neural networks for text summarization, probabilistic programming for understanding housing prices and various machine learning approaches for journalism.

Kumar Sambhav Shrivastava photograph

Kumar Sambhav Shrivastava

India Research Lead

Kumar Sambhav is a journalist and social entrepreneur. He is the founder of Land Conflict Watch, an interdisciplinary research organisation in India, and was the co-founder of The Reporters’ Collective, a non-profit investigative-journalism collaborative. He was also an inaugural Artificial Intelligence Accountability Fellow at the Pulitzer Center. Kumar has reported for prime global and Indian news outlets, including Al Jazeera, Huffington Post, Business Standard, Hindustan Times, Down To Earth and The Times of India. For his reporting, Kumar has received the prestigious Red Ink Award, the Press Council of India’s National Award for Excellence in Journalism and the Shriram Award for Excellence in Financial Journalism.

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