The European Court of Justice set out the general rule for these decisions in 2014: the search engine which lists results leading to information about a person must balance the individual’s right to privacy against Google’s (and the greater public’s) right to display / read publicly available information.
The bigger issue though is the – almost deliberate – lack of clarity. Each person’s details need to be considered on their own merit, and a decision made based on this balance between the rights of the individual and the rights of the wider society, based on a subjective consideration of the original crime, the persons actions since and the benefit to society as a whole. This is further complicated by the fact that different rules will apply in different countries, even within the EU, as case law diverges. The result: Google is likely to face challenges if it takes anything other than a very obedient approach to those requests to be forgotten which it receives.
–Google or Gone: UK Court Rules on ‘Right to be Forgotten,’ Data Protection Representatives (DPR), by Tim Bell, April 16, 2018