100% of innocent people can choose not to take a plea deal. The fact that some innocent people might take plea deals anyway is a way of managing your downside. That seems reasonable.
> 100% of innocent people can choose not to take a plea deal
But innocent party A can't choose not to have a third-party B take a plea deal in which testimony that reinforces the prosecution of A is rewarded with a lighter sentence for B than a guilty plea without such testimony would get.
So you're saying that plea deals encourage people to lie under oath? That seems like an entirely different problem from innocent people pleading guilty.