I believe that there has to be some extra concern for those killing cops. They lay their lives on the line daily; and when the crooks feel no special fear in killing a cop, they won't be so "respectful" of the badge.
All life is equally precious; but there needs to be some special deterrent for taking the life of one who daily stands up between us and the really bad guys.
Again, I truly understand your sentiment. But if one steps back and looks dispassionately, it is clear that the real problem is inadequate punishment for murders in general. When we react emotinally by creating "new, superdooper we really mean it this time" laws that assign more worth to some classes of victims than to others, we further deemphasize punishment for murdering "mere" citizens. It only stands to reason that if some people are more valuable, others are less valuable.
Consider this, as well. Cops and soldiers and Marines know the risks they are taking; noboby makes us take the job, and we get paid for it. And we are armed and trained to face such risks. We appreciate your respect, but we are in no way a privileged class -- not under our Constitution. What is truly heinous is the murder of innocent, law-abiding and often helpless citizens we are sworn to protect.
Best to you and yours...