As I have said before on this board there is a very good reason that most spy cases are pled out by the defendants and why the government is eager to do so. Getting spies to tell us what they gave away and how they did it is very valuable and critical in getting an accurate damage assessment. The government hangs a lot over their head, offering lesser sentences for spouses who are involved and threatening to seize everything they own if they were paid seem to be pretty common. With the information that we often gain from convicted spies we can not only gain a more accurate damage assessment but the government can try and implement fixes that the spies and their handlers may have exploited. Think of it like a mishap investigation, there is good reason to make sure those results and everything said in them are protected, in the long run it is much more valuable knowing what happened than hanging someone.
In case anyone cared, these two were pretty unusual for modern-day spies in this country. First, they did it for ideological reasons and second, they were moles. The husband specifically joined State's intel agency at the behest of Cuban intelligence. Off the top of my head there has only been one other spy (maybe two, but the other was an idiot) in the US recently who did it for ideology and no other moles that I can think of in recent times. Something you see in spy novels often but not so much in real life, though in fiction the spy usually isn't an idiot who fails to hide his real ideology.
