Oh come the heck on, it’s a standard British Category A prison. Any comparison to Gitmo are prima facie ludicrous and makes the rest of the article suspect
"Between 2001 and 2002, Belmarsh Prison was used to detain a number of people indefinitely without charge or trial under the provisions of the Part 4 of the Anti-terrorism, Crime and Security Act 2001, leading it to be called the "British version of Guantanamo Bay"."
Perhaps there should be a time limit when people should forget that their government imprisoned people without trial or charges, however I suggest it should be greater than 21 years.
"Between 2001 and 2002, Belmarsh Prison was used to detain a number of people indefinitely without charge or trial under the provisions of the Part 4 of the Anti-terrorism, Crime and Security Act 2001, leading it to be called the "British version of Guantanamo Bay"."
https://en.wikipedia.org/wiki/HM_Prison_Belmarsh