American software giant Microsoft has sued the US government for trying to breach the privacy of users by seeking to read their personal emails and other personal data. And to compound the issue, the government is restricting the company from sharing or informing the affected users about the US government’s action.

In the lawsuit filed at the federal court in Seattle, MS questions the legitimacy of the Justice Department in seeking secrecy in such cases of surveillance.

“We believe that with rare exceptions, consumers and businesses have a right to know when the government accesses their emails or records,” Microsoft president and chief legal officer Brad Smith noted in a blog.

Microsoft pointed to the rising personal data use of US government by targeting data stored in the cloud. It cited 2,576 instances of such use in the past 18 months, reports USA Today.

Arguing that the Electronic Communications Privacy Act of 1986 as unconstitutional and violative of the Fourth Amendment, Microsoft said it tramples upon the rights of users to be informed by the vendor if there is a need for sharing data.

Microsoft had been very vocal in supporting Apple’s battle with the US government on FBI wanting to break the encryption of iPhones.

The DoJ reacted that the federal authorities are “reviewing’’ the court filing, according to spokeswoman Emily Pierce.

Meanwhile, a body of Federal investigators defended using such data from tech companies while probing serious crimes like child pornography and terrorism.

Donald Mihalek, executive vice president of the Federal Law Enforcement Officers Association said cyber evidence in such cases is absolutely necessary.

Gartner Research analyst Avivah Litan regretted that the US laws have not kept pace with the Internet revolution and hailed Microsoft’s determination to challenge outdated laws.

Meanwhile, a report in the New York Times sought to differentiate Microsoft’s legal battle with that of Apple’s fight with the FBI over iPhone encryption issues.

It noted that the software giant is challenging the whole legal process around secrecy orders and not fighting a solo case. The lawsuit will also give a fillip to the debate on balancing customer privacy and law enforcement needs, it said.