In this case there was a question of threats to the defendant’s safety.
'The judge said in his ruling that he had examined “raw underlying intelligence material” before deciding there was not a “real and immediate risk” to NX121 or his family if his identity was made public.
Lucraft said the three-month delay in naming the officer would allow for “the imposition of any additional mitigating measures to be put in place.”'
Source: https://www.theguardian.com/uk-news/2023/oct/30/met-officer-...