It's a legal system, not a justice system.
One way of at least improving the situation would be for laws that would allow for the victim to sue both the State and public officials separately. If police and other public servants could not hide behind the protection of State and could easily be sued for negligence then they'd be much more diligent. It wouldn't make things perfect but it'd only take a few instances of public servants finding themselves out of pocket to the tune of their life savings for things to improve significantly for the better.
There's no doubt that democracy is badly impacted by such events, and it's little wonder that people continue to lose faith in their governance whenever this happens. Anyway, I hope some smart lawyer will make the State pay very early for its irresponsible and horrendous error and that Spriestersbach is awarded the large compensation that he deserves.
I think justice should be considered the entire purpose of a legal system. And if it isn't working, it should be fixed.
Accountability sounds like a good place to start. If an official causes harm to another person through negligence or otherwise they should be held accountable to the same standards as anyone else.
... but it doesn't always succeed for multiple reasons. One of the most common being that it's not always possible to grant all parties justice. Sometimes, courts have to evaluate a zero-sum situation and decide how cost will be shared, so there's no way to move forward without constraining someone's rights. And people's definitions of "justice" vary, and are far more often grounded in emotion than coherent philosophy... It's not always even logically possible to grant all parties justice.
The useful distinction to keep in mind is that the legal system will follow the law, but whether the outcome of that is "justice" is a subjective evaluation more than a measurable concept.
This is probably argument from definition (unclear) but in any case, it's a statement which needs backing up.
To cite a usual boogeyman for such discussions, the Soviet court system under Stalin wasn't at all interested in justice.
It's not clear to me that the incentives in the US court system align with justice more than accidentally. As in, sometimes the guilty go to prison, as a side effect of the prosecutor's office needing to clear their docket and present good numbers to keep their budget up. Very occasionally, the innocent are cleared of crimes, and even more occasionally than that their lives aren't ruined in the process; defense attorneys want to look good as well.
And, to play Devil's advocate, most of those in power under Stalin would likely have claimed and honestly believed that it was a justice system and that it was using its might for the greater good.
Outright sociopaths who simply don't care about harm are rare. When systems cause more harm than good, it's usually because well-intentioned participants fall prey to other human flaws:
* Dehumanizing and believing that some groups are simply less worthy of care than others.
* Biased data or beliefs about who is harmed and who is helped.
* Principle-agent problems where the ones making the decisions don't see or own the consequences of them.
* Emergent properties where no individual member of the system wants a result, but the system as a whole ends up producing it because of its structure. Sort of the beauracratic equivalent of crowd crush.
The reason I'm pointing this out is because I think when non-totalitarian systems fail to help, it's usually for the same reasons. It's not because of psychopathic monsters. It's mostly that primate brains were never designed to operate at the organizational and power scale we have created. The fact that it works at all is a miracle.