The Culture Secretary has condemned the use of the Regulation of Investigatory Powers Act to find journalists' sources.
Speaking at the Society of Editors conference in Southampton this morning, Sajid Javid said RIPA is "being used in a manner for which it was never intended".
It has emerged in recent months that four police forces, and one local council, have used RIPA to spy on journalists.
Javid said: "The right to keep sources anonymous is the bedrock of investigative journalism. Without it, you cannot do your jobs. Without it, the corrupt and the crooked sleep easier in their beds.
"It’s a sacrosanct principle and one that the authorities need a damn good reason to interfere with.
"RIPA was passed to help with the fight against serious criminal wrongdoing.
"Not to impede fair and legitimate journalism, no matter how awkward that journalism may be for police officers and local councils."
He added: "The legislation should never be used to spy on reporters and whistleblowers who are going about their lawful, vital, business."
Javid said he supported Home Secretary Theresa May in "doing what she can to stop this happening".
He said: "As the Secretary of State responsible for the media, I’ll be making sure the Home Office knows just how important this issue is for the industry.
"And I’ll be watching closely to ensure the Act is not misused in future."
The Conservative MP also condemned the "right to be forgotten" ruling in the European Court of Justice and and the prevalence of Town Hall "pravdas", citing them as other "threats" to the journalism industry.
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