The prosecutors decided that Google's actions were involuntary
Google's Street View WiFi blunder continues to haunt it to this day. The initial uproar died down eventually, with most government agencies deciding not to press charges or fining the company some inconsequential sums.Things got stirred up again earlier this year, ironically, by the conclusion of an FCC report in which the agency decided not to go any further with the investigation.
The report indicated that some people at Google should have known that Street View cars were collecting payload WiFi network data, despite Google claiming that this was done unwillingly.
This revelation, of incompetence, not necessarily malevolence, spurred several other agencies to restart their investigations. These new investigations led nowhere and were dropped eventually.
This is the case in Germany, where prosecutors, who have been some of Google's and Street View's most ardent critics, even before the whole WiFi fiasco, finally decided to drop (in German) the investigation and the possibility of a full blown suit against Google.
The prosecutors have been investigating the matter for two years. They concluded that since the data was public, no law was breached and that Google's actions were accidental, what the company said all along.