Dataharvest 2026 - the European Investigative Journalism Conference

A leak of several million emails from the Israeli Ministry of Justice revealed a long-running lawfare operation aimed at shielding Israeli policies toward Palestinians from legal scrutiny in international and European courts, while also seeking to criminalize protest and advocacy against Israeli human rights violations. Spanning nearly 15 years and involving more than a dozen European countries, the emails are written mainly in Hebrew and show how several European countries collaborated with Israel to ensure impunity for its illegal occupation, paving the way to future war crimes. Media in Israel-Palestine are barred from reporting on the leak due to a gag order, making international collaboration essential. The leaked collection of MoJ documents have been indexed and made searchable for the public in the Library of Leaks by the nonprofit whistleblower site Distributed Denial of Secrets (DDoS).

This session presents how an independent journalist, working with European Investigative Collaborations (EIC) and multiple European newsrooms, analysed and reported on the leak using straightforward, accessible methods. The investigation relied primarily on close reading, systematic memo-writing, manual timeline construction, and country-by-country mapping of key actors and legal strategies, complemented by cross-referencing the emails with publicly available records.

The talk will share practical lessons on making sense of large email leaks in multilingual contexts, combining leaked material with open-source and public-domain data, coordinating cross-border reporting under legal constraints, and maintaining accuracy through repeated verification and collaborative review.

Large language models (LLMs) have become a common tool in most investigative newsrooms. But what do you do when prudish language models refuse to process what you are investigating? Or you have so much sensitive information that it makes your stomach hurt to send it to Big Tech?

Enter local AI models!

Norwegian Broadcasting Corporation (NRK) has used AI models running on their own machines or leased ones to carry out several projects. Together with Lighthouse Reports, we exposed a hidden class divide in Norwegian courtrooms – revealing that the wealthy receive more lenient sentences than the poor – by analyzing 9,000 verdicts. The NRK team then turned its attention to the adult industry, reviewing over 1,000 films to document a sharp rise in choking incidents.

While the subjects differ vastly, the projects share a common thread: the controlled use of local AIs to process massive datasets. We want to share our methodology, our findings, and insights along the way – but most of all demonstrate how to get you started with using the latest local models for your specific investigative needs.

In the presentation, we will show concrete examples of how to run the latest local models and invite the audience to think with us about how these models can enhance investigative workflows.

This talk will show the methodology behind The Guardian’s exclusive investigation into properties advertised as tourist destinations on Airbnb and Booking.com located in Israeli settlements that are illegal under international law. The Guardian found 760 rooms being advertised in hotels, apartments, and other holiday rentals in illegal Israeli settlements in the West Bank, as NGOs and activists warned that these companies are violating international law and profiting from war crimes.

In their investigation, they used geospatial tools, like PostGIS and QGIS, to localise accommodations on a specific geographical area, and to join these accommodations with shapefiles representing the borders of illegal settlements to identify those based within settlement boundaries. Using OSINT methods and Google Sheets, they designed a methodology to solve data challenges like duplicate and multi-platform listings, and listings with approximate locations.

In this session, attendees will come up with a robust methodology to find tourist accommodations in any geographical area, so they can reproduce the method for new stories.

Police work is notoriously difficult to investigate. While police actions directly affect fundamental rights and guide politics and law-making, official data on their influence is scarce.

In this session, we will share some tools and methodologies on how to investigate the police sources. We will draw on more than ten years of investigations into different aspects of police violence and state abuse of power in Germany. We will also show how the data-driven journalism tools can help to make the underlying structures more visible, and present our recent investigation into police unions in Germany: who they are, want they stand for and how they influence the public debate and politics. We pieced together data from different sources and combined it with investigative journalism to draw the full picture.

We want to show how it is possible to do a data-driven investigative story despite missing data. We will focus on the following questions:

- How to build your own datasets when no official statistics exist? Which public data sources about the police are available? Which data can we get from ministry inquiries? What about social media?
- How to clean up, classify and analyze the data? Which tools are helpful in combining manual and automated workflows?
- How to tell a complex data-driven story without this one headline? What are judicial and editorial hurdles when publishing a sensitive topic?
- What can investigative and data journalists gain from close collaboration? What worked well? What would we do differently?

What really happens behind the glossy surface of OnlyFans — and how do you investigate an industry built on secrecy, money, and blurred consent? After more than a year of reporting on the hidden economy around OnlyFans across five countries, I will take participants inside a world of agencies, chatters, fake identities, reseller servers, and leaked-content markets that platforms never talk about.

This session reveals how intimacy becomes a trap: how creators are manipulated by intermediaries, how their content is redistributed through underground Discord and Telegram networks, and how money flows through a web of crypto, burner accounts, and anonymous middlemen. Using findings from the cross-border investigation, From OnlyFans to OnlyScams, we will show how to uncover what the platform hides.

What attendees will take away:
- Investigating online sex-work ecosystems ethically and safely
- Techniques for undercover reporting, digital tracing, scraping, and mapping hidden networks
- Following payment trails and linking them to real actors
- Interviewing victims and insiders without causing additional harm
- Turning a sensitive, high-risk digital investigation into a powerful cross-border story

This is a practical session for journalists who want to explore one of the fastest-growing — and least understood — shadow economies on the internet.