In the non-binding decision, the adviser to the European Court of Justice said the tech company was bound by European Union (EU) privacy laws but did not have to delete sensitive information from its search indexes.
The court — Europe's highest — issued a statement explaining the decision which stated : "Requesting search engine service providers to suppress legitimate and legal information that has entered the public domain would entail an interference with the freedom of expression."
"Search engine service providers are not responsible, on the basis of the Data Protection Directive, for personal data appearing on web pages they process," the court said in its advice.
"This is a good opinion for free expression," Bill Echkison, a spokesman for Google, said in a statement.
"We are glad to see it supports our long-held view that requiring search engines to suppress 'legitimate and legal information' would amount to censorship," he said.
The EU court is expected to hand down its final judgement on the matter by the end of 2013.
Eighty percent of such advice is accepted by the court's judges, reported Spanish national daily El Pais on Tuesday.
The opinion comes in the wake of action launched against Google by Spain's date protection agency, the APGD in 2010.
The agency had demanded that Google delete any search results linked to a property auction notice in a newspaper, El Pais reported.
By doing so, the AGPD was responding to a petition brought forward by a private citizen in Mario Casteja.
Casteja said his right to privacy had been infringed by the continued online existence of a notice about his home being dispossessed.
He said the matter had been resolved, and that the article should now be deleted.
The AGPD took action against Google, but refused to delete the original article saying that its purpose had been to raise the maximum amount of money through tenders, and was therefore in the public interest.
In related news, Spain opened sanction proceedings against Google on Thursday for suspected serious breaches of data protection laws, acting just hours after France threatened the Internet giant with fines.
The agency said it acted after investigating Google's new policy, introduced last year, which enables it to track the activity of users across its search engine, Gmail, the Google+ social networking platform and other services it owns, which include YouTube.
The changes make it easier for Google to collect and process data that could be used by advertisers to target individuals with offers tailored to their specific interests, thereby increasing the company's revenue potential.
Spain said Google Spain and Google Inc.'s new policy could allow it to combine personal information collected from different services and use it for other ends.
"Google does not give clear information about the use it will make of users' data, so they are unable to know precisely why their personal data is being collected or how it will be used," the agency said in a statement.