The presumption of innocence and the requirement for proof beyond a reasonable doubt were created to protect us from governmental criminal process. It was not intended and does not go further. I'm not bothered when someone who kills someone pays for it civilly even if he is found not guilty.
In this case, I feel your analogy is a little off the mark. It's more similar to someone who is acquitted of murder but still labeled a murderer... or someone who is charged with a rape, proves his innocence, and is still placed on the sex-offender list.
The arrest is exactly governmental criminal process, and maintaining its record is, as well.
"Have you ever been accused of being a witch?"
"Well, this one time in third grade, Nancy Harrington was being a brat, and..."
"BURN THE WITCH!"
Apropos civil judgment, I have no problem with someone being acquitted of murder but convicted of wrongful death, but I do have an issue with arrests being used as a metric to establish a "pattern of behavior".
We give too much priority to negative-weighting criteria—in my world, an arrest would have zero legal significance alone, and officers would bear some degree of liability for who and when they arrest. For my part, I don't think the bogeyman of legions of criminals wandering the streets because they gamed the system is real, significant, or—if it
were real—truly bad. Involving someone in the legal system is incredibly injurious, and with our rates of incarceration, the degree of "recidivism" we purport, and the inefficiencies of our entire legal process I can't help but think of the law as just another avenue of exploitation, and our bar for PC touching the ground.
Furthermore, even if record of arrests was presumably neutral, I would argue that using those records as a basis for employment would be potentially unfairly discriminatory against protected classes.
Just my opinion, as uninvited and out-of-place as it is here.
Sorry for wasting your time with my sidebar!
-Fox