In the UK we have minimum terms. Basically the life sentence stands and if released on parole (after the minimum term) then they will be on licence which means they can be returned to prison at any time if it is believed they present a danger in general or break the terms of their licence, without trial.

We do have whole life terms but they are reserved for the most serious murders, such as serial killers

These particular killers seem to want the fame/infamy. Keeping them anonymous is actually a worse punishment for them.