The Challenge of Child Porn on the Bitcoin Blockchain: Legal and Technical Questions

Recently, the cryptocurrency community has been focused on a confusing issue: the presence of prohibited content related to child porn encoded within the Bitcoin blockchain. The question is not simply technical – it has reached legal implications for those operating full Bitcoin nodes.

The controversy began when Ethereum developer Vlad Zamfir posted a Twitter poll containing a powerful question: “Will you stop running your full node if you find out there is child porn encoded in the blockchain?” The poll received 2,300 responses, and the results showed that only 15 percent were willing to stop.

What Exactly Is Found on the Blockchain?

A study from RWTH Aachen University released alarming results: they discovered a graphic image and 274 links to content depicting child abuse stored within the Bitcoin blockchain. But understanding how exactly this is stored is important.

Child porn and other prohibited content do not appear as download-ready files or videos that can suddenly pop up on your computer. Instead, the offensive content is encoded and stored as cryptographic links and random text strings embedded with other data within transactions. To access or reconstruct the actual content, a person must:

1. Know exactly where the encoded data is stored
2. Have the technical knowledge to decode it
3. Actively attempt to reverse-engineer this information

Due to this complex process, Coin Center’s study clarified that a copy of the blockchain does not literally contain images, but rather contains random text strings that, if decoded by someone knowledgeable, can be restored to their original form.

The Legal Path: SESTA-FOSTA and Legal Implications

The emergence of child porn on the blockchain raises serious legal questions, especially in the United States. The most relevant legal framework is the SESTA-FOSTA (Stop Enabling Sex Traffickers Act—Allow States and Victims to Fight Online Sex Trafficking Act).

Before SESTA-FOSTA, Section 230 of the Communications Decency Act provided protections for Internet service providers (ISP) and other users against liability for content left by others. But SESTA-FOSTA created new challenges. RWTH Aachen University’s report does not directly specify any country, but the implications are particularly clear in the U.S., where participation in the network as a miner or node operator could potentially be illegal if one has knowledge of child porn.

Cardozo Law School professor Aaron Wright provided critical insight: “This is part of the tension between the difficult-to-change data structure, the blockchain, and the requirements of certain legal pockets.”

The importance of legal intent should not be overlooked. Princeton professor Arvind Narayanan tweeted that the mainstream media response is “not surprisingly shallow.” He emphasized that “Law is not an algorithm. Intent is a crucial factor in determining legality.”

Most U.S. laws, as Wright points out, hold individuals responsible only if they “know they own” or produce, sell, broadcast, or access content “with the intent to view.” Since most Bitcoin users have no idea which data on the blockchain contains child porn, many believe the legal framework is irrelevant here.

How Other Blockchains Are Facing the Same Problem

It is important to note that this issue is not exclusive to Bitcoin. Almost all blockchain networks allow data to be added to transactions, meaning anyone with technical skills can add the same type of child porn content to any open-source blockchain.

Ethereum, Litecoin, and other cryptocurrencies all have the same potential vulnerability. The problem is not with blockchain technology itself, but with how any decentralized network cannot fully control what data is added.

Solutions Being Explored by Developers

As concerns grow, the developer community is working to find practical solutions. Cornell University professor Emin Gun Sirer explained that “regular cryptocurrency software” lacks the tools needed to reconstruct content from specific encoding.

Bitcoin developer Matt Corallo suggested several options:

1. Encryption: If possessing encrypted data is legal, encrypting the data alone could solve the issue for node operators who do not want to see decoded content

2. Hash-only Storage: Network participants could choose to store only the “hash and side effects” of transactions instead of the full content

3. Selective Pruning: Advanced solutions could allow users to prune or not store the content of suspicious transactions

But Corallo emphasized the need for clearer legal guidance: “There needs to be more clarity on what exactly is illegal before developers can address these issues.”

The Community Responds: Who Is Responsible?

The Vlad Zamfir poll provided a window into how the cryptocurrency community views the problem. The fact that 85 percent said they would stop indicates high ethical awareness, but it also raises the question: should they have a legal obligation to do so?

A critical point: if a node operator or miner personally adds or knows that others are adding child porn to the blockchain, they have a legal obligation to alert authorities. But the pseudonymous nature of Bitcoin makes it very difficult to track and de-anonymize malicious actors.

Wright suggested a solution: “If you record this information on a blockchain, you often have a record of who uploaded it. Similar to issues related to tax evasion or funding terrorism, you can mine through the blockchain and attempt to de-anonymize the party who uploaded it.”

The Larger Lesson

The challenge of child porn on Bitcoin is part of a larger tension between decentralized structures and legal requirements. In Europe, the problem could also manifest in the right to be forgotten. In the U.S., it is emerging through various laws concerning sexual content.

But one thing is clear: as cryptocurrency adoption continues to grow, questions about child porn and other prohibited content on the blockchain will not go away. Solutions will require collaboration between developers, legal experts, and law enforcement to find a balance between decentralization principles and protecting vulnerable groups.

A blockchain is unlikely to be a good place to store obscene or inappropriate information related to child porn – but as long as the technology remains open and immutable, this challenge will persist until the community finds practical and legal answers.