I think AM pretty much counted on the shield of invincibility that his generational family heritage gave him. In his mind, nobody would really investigate because of the strong family influence in the area. (It may have shielded or protected them in the past from other suspicious deaths. IMO.) And I think the family influence did buy him time because I think LE was still deferential to a point. As a lawyer, he knew that he would be a "suspect" from being the husband/dad, as well as being the ones to report the deaths. But, he figured he wouldn't be thoroughly investigated and probably thought that tossing out ideas like retaliation for boat death/accident would be good enough to keep it in the SODDI/nebulous "bad guy" territory forever and ever.
I think the only thing the defense can reasonably argue at this point is that LE overlooked a lot of stuff/didn't test certain things/made more allowances (lots of people at Moselle the next day, for example) than might normally be given, etc.
Regardless, all the evidence points straight to AM.
Really have to wonder how many more family skeletons are in the closet, waiting either to be further/better hidden or fall out into the light of day.
MOO.