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.


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.

Angie Waller photograph

Angie Waller

Product Lead and Research Manager

Angie has led teams of researchers, journalists, and engineers at various organizations, including New York University's Center for Social Media and Politics, The Markup, and Data & Society Research Institute. With a background in art, computational linguistics, and user experience design, she brings a unique perspective to studying online environments. Her work with The Markup on Citizen Browser, a custom Facebook data collection application, has been recognized with an Edward R. Murrow award for Excellence in Innovation. Angie enjoys sharing her research with broader audiences through art publishing under the imprint Unknown Unknowns. These volumes are available online and at independent bookstores worldwide.

Qazi Firas photograph

Qazi Firas

Research Associate

Firas is an architect and digital humanities professional, specialising in mapping cultural histories through games, archives, and digital storytelling. Firas employs innovative digital mediums to explore and preserve cultural narratives. His background seamlessly blends design and cultural understanding, providing a unique perspective to his work and fostering a dynamic approach to bridging traditional cultural histories with the digital realm. Firas has led diverse projects, including mapping endangered languages in India and crafting web-based text games portraying citizens’ socio-political interactions.

Pallab Deb photograph

Pallab Deb

Research Associate

Pallab is a social-science researcher whose research focuses on technology, Indian politics, and urban policy. He has previously worked at Nagrika, a think tank; and the Indian Political Action Committee (I-PAC), a political consultancy. At Nagrika, his research delved into decentralised governance and sustainable transportation in Tier-II and Tier-III Indian cities. In his role at I-PAC, he conducted analysis of constituency-level data, drawing insights based on demographic nuances, voting patterns, and local influencers. Pallab was also a fellow at the Indian Institute for Human Settlements, where he researched on urban housing and infrastructure.

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