So you assert this is what happens in "many" political cases, do you? What actual evidence do you have of that? Do you have links to any credible studies supporting that, or is this more speculation on your part? And I don't mean a link to just one particular case, but rather a study that shows that this occurs in "many" political cases.
As for a news report that says a "no true bill" finding means the suspect was found "not guilty" that would mean the reporter was grossly misinformed on what a "no bill" finding means. It is not a determination of guilt. It is only a determination that insufficient evidence was presented for the jury to find probable cause. Unlike an actual verdict of not guilty, a no true bill does not preclude the state from trying again later when it has more evidence to present.
You have already made up your mind that murder charges are appropriate even though we do not have nearly all the evidence in this case yet to determine that. Thank God you are not one of the investigators. Investigators that make up their minds on incomplete evidence are among the worst investigators because they then look for evidence to fit the outcome they want rather than getting all the available evidence first and then weighing that evidence objectively to determine what likely occurred. The latter is what good investigators do.
Let's wait for all the evidence before determining the degree of guilt.