In the past few weeks, we’ve seen a lot of visionary blockchain talk, particularly at Ethereum’s DevCon conference in London. Disclaimer: I am still working my way through the wealth of content that was recorded over the five days.

It is becoming apparent that there is seemingly limitless potential for many events and transactions in our professional and private lives to be recorded in these huge distributed computers.

While the transparency and security of blockchain tech are powerful arguments for the adoption of these systems, it is going to take a paradigm shift in thinking to embrace such change, particularly among people who don’t understand the technological implications.

Take defamation law, for example. Before my life as a technologist, I was a journalist: first working in print and then embracing the huge, exciting changes that overwhelmed the publishing industry with the advent of the internet.

In those years, there were many cases where traditional legal systems struggled to keep pace with rapidly changing technology. The facts on the ground no longer match the edicts handed down from on high, and the global nature of digital media means that legal jurisdiction in one country can be ignored in another. This has obviously had a beneficial impact on transparency, especially in countries where the powerful have sought to limit public knowledge about their activities.

There have been various cases in the UK where British publications have been forbidden to publish various photographs or stories, only for anyone who wanted to be able to access them online where they were published by French or German entities, to the frustration of the legal establishment.

Given the level of technological ignorance possessed by many people working in the legal system, I believe that blockchain-based data storage will create similar challenges in years to come.

I pity the poor technical experts who will one day be called into a court to explain for the first time to a judge and a jury why it is not possible for the “owner of the blockchain” to remove proof of something that is considered defamatory — and, indeed, to explain that the blockchain has no owner who can be taken to court and forced to remove the offending data.

There is no more powerful and immutable proof than embedding a record of an event in a public blockchain like Bitcoin or Ethereum. But what happens in the case where something is embedded into a public blockchain — and then there arises a compelling reason why it needs to be removed?

This thought-provoking read from the Open Data Institute outlines various scenarios where people may want data removed from permanent record: for example, people who have made a transition to a new gender or who would like a previous insolvency removed from record: http://ift.tt/1OkEIFM

The post goes on to say:

“Blockchains do not have to expose personal data directly to reveal private information about people. A blockchain recording visits to health practitioners (including midwives, mental health teams, AIDS clinics) does not need to include the entirety of someone’s health records to reveal information about them. Much like phone records or browsing histories, this metadata may be sufficient to reveal personal details.”

It does not mean that storing this sort of information in a blockchain is a negative thing, only that anyone experimenting in the area needs to think through the implications.

In most cases, the idea that you cannot delete something from the blockchain will not be a problem — simply adding an entry that reverses or negates the original entry would be sufficient. And for cases such as those outlined by the ODI, there are already solutions that could be implemented.

In a world where our history has frequently been rewritten, and where governments have tried to suppress unpalatable facts, the right to transparency should be something that concerns us all.

It is the responsibility of everyone developing blockchain solutions that touch private data to ensure that they are implemented responsibly and that they are not unwittingly providing a weapon for the very people who don’t want transparency and accountability.