At the same time, I'm pretty sure we can find plenty of cases where a retrial is warranted.
Even if you could find any such cases (and I'm sure that you could find a few), the harm to society by allowing retrials greatly outweighs any benefit that might be gained from locking up these criminals.
I do not believe they would stop at just those few either
The slippery slope is too slippery.
I agree, but at the same time, think about it. Someone kills your loved one but gets away with it because of missing evidence. Then, a couple of years later, new evidence is found that unequivocally proves his guilt.
How would you feel?
It doesn't matter how I would feel. In a criminal case, there are two parties: the state and the defendant. The victim (or relatives) only come into play to give statements during sentencing. The important part is safeguarding criminal processes so that they can't be abused by either party, especially the state.
If that's all that's important to you about a criminal process, then I understand why you think it doesn't matter how you feel.
Me, I think that how the citizens feel about their legal system should matter, and matter a great deal. If you don't trust the system, why should you play by its rules?
This is a different argument. How citizens objectively view the system they fund with their tax dollars is different from how a victim (or a victim's family) subjectively views the system that is working to convict someone of a life-altering crime.
Actually it's not a different argument. You simply define the scope differently.
The real question is which system you'd prefer as an innocent (or even guilty) defendant. In the criminal justice system, where the government has the most resources and power, the system should be leveling the playing field for the other side to ensure fair proceedings. While it may be an emotionally compelling argument to think about the victim, both America and England (and, I assume, Sweden and Finland) have long histories of abuse of power in criminal proceedings. These protections aren't arbitrary; they exist for a reason.
Not just emotionally compelling, IMHO. It depends on who you define the system to be for. While you appear to limit the scope to the accused and the state, I think the victim should be part of it.
I was robbed once. Now, they did catch him and they did prove his guilt--the guy wasn't the most sophisticated of criminals, to be honest--but I was part of that case, and it was not just about emotions and such. It was about justice, which really is the whole point. I would have recognised that guy anywhere and if they had botched the evidence or the arrest, the system would have failed me.
I'm not advocating double jeopardy, though, not really. I don't like that idea more than the alternatives.
And yes; I could be wrong, in spite of being sure about his guilt.