We're agreeing to disagree, and that's ok. I don't think that this will ever get to the point of the scifi plot device you think it will be. It's too invasive and requires too much training to be effective.

So it needs a lot of development and patience and literal brain surgery on willing subjects to test this specific use. Medical uses will follow their own niche, making this a point where clandestine research well have to fork it for their own purpose soon. The overhead is massive here, pardon the pun.

Meanwhile, an effective method for getting close enough already exists and is used to prosecute people.

Where is the incentive to spent the years of research to develop this specialized tool further, tailored for the "precrime" purpose? Especially when it's not just quick and easy, but cheap to do this already? There's no urgency or need to do anything else. This doesn't do anything we can't already do.

Edit: You're suggesting something as invasive as the famously unsuccessful MK Ultra program. Meanwhile, using money and black mail remain widely used ways to manipulate someone. The bar is already set high by low-tech means.

Ooooh, did you listen to the EFF podcast and that's why you're all about this?