Whistleblower protections were expanded to more employees at federal contractors last month, meaning companies in the defense industry and others will have to be on high-alert for retaliation against employees who raise concerns.

The National Defense Authorization Act for fiscal year 2013, signed into law by President Obama on Jan. 3, substantially enhances whistleblower protections for a wider range of federal contractor employees than previously covered, underscoring the need for robust internal controls to effectively address reports of misconduct.

The law extends whistleblower protections to Defense Department and National Aeronautics and Space Administration sub-contractors, where only direct contractors were covered before. ...