If you've reported colleagues for suspected bribery to your institution's Vigilance department, you might be concerned about potential defamation claims. The risk of a defamation case depends on whether your complaint is proven true. If the complaint is unsubstantiated, the accused may have grounds to sue for a false and frivolous complaint. It's advisable to await the outcome of the Vigilance department's investigation before taking further action or worrying about defamation threats.