Troels Oerting, assistant director at Europol and head of the European Cybercrime Centre, has said that the Edward Snowden revelations and the rise of encryption and anonymity are making cybercrime investigations more challenging.
Oerting told the BBC in an interview that Europol believes there is a hardcore of some 100 cyber criminals out there and that it would be easier to take them down if there was a reasonable distinction between a right to privacy and the unacceptable use of anonymity tools.
He said that people have confused privacy with anonymity since Edward Snowden began making his PRISM revelations, and that the criminals have an advantage because of this confusion and have been given a pass by the "good guys of the internet".
Oerting suggested that the security agencies should have the right to access anonymous accounts, but that this should happen only with some judicial oversight.
"They have an advantage," he said. "You have a right to privacy, but that does not mean you have the right to be anonymous. There must a possibility for law enforcement with a warrant from a judge to actually access some information."
He added that the increased use of encryption is making it "difficult" for everybody, including the police.
The rise of encryption has been welcomed by web users and the security industry, and does not seem to present much of a challenge to other investigating security agencies.
A large number of technology firms are rolling out two-factor authentication and encryption, and asking for more judicial oversight on warrants.
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