Setting: Modern-day London
Research: Wikipedia for spousal privilege and conspiracy, as well as watching Law & Order UK to get a feel for the criminal justice system as a whole (and in the hope there would be something pertinent; there wasn't). Not sure where else to look/ how to search for my question.
I've read what Wikipedia has to offer on spousal/ marital privilege and come away with the fact that a married person cannot be compelled to testify against a spouse. My question is this: how would that work if the couple were co-defendants?
My scenario: two friends are charged with conspiracy (I'd like to keep things as vague as possible; I know a married couple cannot be jointly charged with conspiracy if they are the only two being charged, but at the time of the crime and when the charges were brought they weren't married) after one helps the other fake his death and they decide to get married so one wouldn't end up incriminating the other.
Does being 'compelled to testify' mean simply appearing as a witness? Can a defendant refuse to answer a question on the grounds that it might incriminate them or their spouse, or have their barrister object/ have the question be disregarded by the jury?
I'm looking to keep about the level of realism as television, but I'd like to know if this scenario is even plausible.