The FBI breached its own internal rules when it spied on campaigners against the Keystone XL pipeline, failing to get approval before it cultivated informants and opened files on individuals protesting against the construction of the pipeline in Texas. Internal agency documents show for the first time how FBI agents have been closely monitoring anti-Keystone activists, in violation of guidelines designed to prevent the agency from becoming unduly involved in sensitive political issues. The hugely contentious Keystone XL pipeline, which is awaiting approval from the Obama administration, would transport tar sands oil from Canada to the Texas Gulf coast. It has been strongly opposed for years by a coalition of environmental groups ... who have been monitored by federal law enforcement agencies. Mike German, a former FBI agent ... said [the documents] indicated the agency had opened a category of investigation that is known in agency parlance as an "assessment". Introduced as part of an expansion of FBI powers after 9/11, assessments allow agents to open intrusive investigations into individuals or groups, even if they have no reason to believe they are breaking the law. German ... said the documents also raised questions over collusion between law enforcement and TransCanada. "These documents suggest the FBI interprets its national security mandate as protecting private industry from political criticism," he said.