A former defence contractor emailed classified details of a British missile system that could have been used by enemies of the UK to counter any attack, a court heard on Tuesday.
Software engineer Simon Finch, 50, sent details of the system, described as critical to UK security, to undisclosed recipients in October 2018, London’s Old Bailey court was told.
Mr Finch, from Swansea, Wales, denies breaching the UK’s Official Secrets Act. He is also accused of refusing to give British authorities access codes to three electronic devices.
"The document he attached to the email set out technical detail classified as secret and top secret... (and) contained detail about the operational performance of the system," prosecutor Mark Heywood told jurors.
"Expert evaluation has concluded that the release of information of that kind, for example to a hostile adversary of the UK, would give them an understanding of the function of that relevant system, which in turn would allow them methods of countering it."
Mr Heywood said the disclosure could create a "risk to the UK and to others with whom that technology is shared".
The jury will hear more details about the system during closed sessions of the court. Journalists and the public will be barred from those proceedings.
Mr Finch worked for private contractors, including BAE Systems and QinetiQ, from the late 1990s until 2018.
Armed with "expert technical ability", he was involved in the design, testing and configuration of the UK missile system still used by British armed forces, according to Mr Heywood.
