A collection of experts and academics has written to Google asking the company to be more open about the way it handles right to be forgotten requests.
The open letter asks Google to bring the process further into the light. The group has picked Google because it believes that the firm is the most informed about the situation. But the request for information applies to all the involved parties.
Google welcomed the input, saying that the way that it responds to requests must always be changing.
"We launched a section of our Transparency Report on these removals within 6 months of the ruling because it was important to help the public understand the impact of the ruling," said a spokesperson.
"Our Transparency Report is always evolving and it's helpful to have feedback like this so we know what information the public would find useful. We will consider these ideas, weighing them against the various constraints within which we have to work-operationally and from a data protection standpoint."
The letter is signed by experts including Ian Brown, professor of information security and privacy at the University of Oxford, and a regular cyber security commentator, and Paul Bernal, from the University of East Anglia School of Law, and follows the release of transparency information about the process.
The signatories are concerned that, while Google has revealed some information about the URL removal process, there must be more to come. It said that the examples Google has given (see below) are mostly old and already publicised.
"While Google's decisions will seem reasonable enough to most, in the absence of real information about how representative these are, the arguments about the validity and application of the right to be forgotten are impossible to evaluate with rigour," they wrote.
"Beyond anecdote, we know very little about what kind and quantity of information is being delisted from search results, what sources are being delisted and on what scale, what kinds of requests fail and in what proportion, and what Google's guidelines are in striking the balance between individual privacy and freedom of expression interests."
The experts are asking Google for more precise information, including aggregate data for study. They said that, without information, including details of the individual cases or topics involved, it is "impossible" to have an informed debate.
"Google and other search engines have been enlisted to make decisions about the proper balance between personal privacy and access to information. The vast majority of these decisions face no public scrutiny, though they shape public discourse," the letter added.
"What's more, the values at work in this process will/should inform information policy around the world. A fact-free debate about the right to be forgotten is in no one's interest."
Google revealed this week that it has received almost one million URL takedown requests and complied about 40 percent of the time.
The controversial right to be forgotten ruling has been accepted reluctantly by Google, and the firm has spent much of the past year questioning its obligations.
The transparency announcement, published on the anniversary of the European Court of Justice ruling, revealed that the firm has complied with 253,617 requests concerning 920,258 URLs.
Google broke down the numbers, showing that the company received 'removal evaluations' for some 126,000 URLs in the UK adding up to around 32,000 requests. The requests were complied with approximately 30 percent of the time.
The firm revealed some details that shed light on individual requests. "A media professional requested that we remove four links to articles reporting on embarrassing content he posted to the internet. We did not remove the pages from search results," Google said.
An example when Google did comply concerned a quashed conviction. "An individual who was convicted of a serious crime in the last five years, but whose conviction was quashed on appeal, asked us to remove an article about the incident. We removed the page from search results for the individual's name," the firm said.
The transparency report includes a top 10 list of target sites, and Facebook came first with 6,772 links removed. Other sites in the top 10, which accounts for eight percent of all requests, include Google+, Google Groups, YouTube and Twitter.
The right to be forgotten had an immediate impact on Google and, while the firm has asked for assistance and guidance on how best to manage the obligation, it did not take long for the requests to start coming in.
Google revealed that tens of thousands of demands came its way within the first few weeks.
Much of the talk in Europe since that time has been about extending the remit of the right to be forgotten to .com domains, as the European Union wants the ruling to apply worldwide rather than just in Europe.
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