I could be completely wrong but I don’t think that HCW is limited to one attempt, I think it’s an ongoing process of reviews.
I do think that the double jeopardy case or similar is a law in Germany so if CB was acquitted for the murder of MM he couldn’t face trial for that crime again.
I’m sure that
@SuperdadV8 could give accurate answers to both questions.
There is a strong "double jeopardy" principle here in germany, according to the old principle called "ne bis in idem".
The problem is, the german legislative produced a new legal principle or adjustment of the criminal codex, that allows to break the ne bis in idem priciple, if somebody has been aquitted in the past, but modern investigative methods like DNA sampling creates "new" evidence. Evidence, that couldn't be achieved at the time of the aquittal (very short verson!!!)
It's obvious, that the plans of the german legislative don't make all the other possibly involved institutions (solicitors or constitutional lawyers) making wishes for a dancing competition, so courts in charge are checking this "new law" or "adjustment" in relation to principles of the german constitution and european law principles as well. That takes time!
The other question is, if this "adjustment" can be seen as a renunciation from double jeopardy in general and the recent investigations against CB. Why?
There is a recent case in germany directly related to the topic. Someone has been aquitted of an alledged murder of a girl in the early 80's.
Now the prosecutors had the chance to retest some evidence for possible DNA traces due to a new processing of the evidence, that didn't exist in the 80's. And the sample matches the DNA of the aquitted person and the discussion about the "adjustment" of existing legal principles began. But all these circumstances don't fit the MM case at all, IMO.
So yes, HCW has still just one lucky punch and the following steps should be chosen very carefully!