In a recently publishedpaper on encryption, the European Union Agency for Network and Information Security notes that, while encryption might make lawful interception harder, less efficient or ineffective, the implementation of schemes such as key recovery and escrow (aimed to enable interception when encryption systems are used) introduces new technological risks to the IT infrastructure and could also damage the evidence gathered by law enforcement agencies. The paper also points to the fact that measures aimed to ban encryption tools cannot be enforced, because many such tools are already available for free, and algorithms are publicly available and can be used by most programmers to develop their own encryption systems. ENISA recommends that policy makers 'refrain from limiting in any way security features in computer software'.