The Federal Communications Commission (FCC) imposed the penalty last Friday, after finding that Google had collected personal information for street level images without asking permission.
The regulator also found that the US search giant had deliberately not co-operated with the FCC's investigation into the situation, leading to it remaining unresolved.
Street View collected data between 2007 and 2010, by a car driving around the US and later Europe taking photos of locations from public places. The data was later used on the Google Maps and Google Earth services.
Concern was widely expressed about the project, particularly after it emerged that Google tapped into unprotected WiFi networks to mine information, such as location, name and even email details.
After Google admitted in May 2010 that it had collected so-called 'payload data', the FCC launched the investigation into whether it had violated the Communications Act.
According to <The New York Times, the FCC's investigation was left unresolved after the Google engineer in charge of the project cited the Fifth Amendment, which protects US citizens' right to silence.
In an FCC order data from April 13, the FCC said: "Google refused to identify any employees or produce any emails. The company could not supply compliant declarations without identifying employees it preferred not to identify.
"Misconduct of this nature threatens to compromise the commission's ability to effectively investigate possible violations of the Communications Act and the commission's rules."
Google said in a statement that it disagreed with the FCC's "characterisation" of its conduct in the investigation, and claimed that it had handed over information.
"As the FCC notes in their report, we provided all the materials the regulators felt they needed to conclude their investigation and we were not found to have violated any laws," the company said in a statement.
"We disagree with the FCC's characterisation of our co-operation in their investigation and will be filing a response."
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