Good morning. I'll be assisting you with your question.
Clearly, the biggest issue with this hypothetical technology is an illegal search.
For the government to need a warrant to conduct a search (which this would be) the subject of the search must have a reasonable expectation of privacy in the place or thing being searched.
In this case, a person would clearly have a reasonable expectation of privacy in their own thoughts. As such, the government would need a search warrant, supported by probable cause, to "search" someone's thoughts.
Can a warrant be obtained for such a hypothetical devise?
If the police could show that they are likely to find evidence of a crime, I don't see a legal reason why they couldn't.
How can you use a thought as evidence?
If the person is recalling something they did, it could be used as an admission.
What if they are acting the thought, as in a movie script?
As with anything else, any piece of evidence is open to interpretation. Just because there is an alternate interpretation, that does not mean the thing isn't evidence.
So if i am acting a part in a movie about burglars and i am been investigated for burglary the police can use my thought as evidence?
In your hypothetical situation where police have a device to read minds, and if the police had a warrant, I think they could.
Of course, Brady would apply to this.
Of course, no court has addressed this issue since it has never come up before.
True. Brady always applies.
And I would be able to subpoena the devise and records?
If they existed, yes, a person could subpoena such records.
What if the technology was being used without a warrant and no official say so as to its usage? How can a challenge be made?
The evidence of one's thoughts would have to be brought into court for it to be challenged, in which case its existence would be outed.
What if its being used indirectly, covertly, to give opposing counsel an edge during adversarial proceedings?
If there nobody is willing to admit to it, and people are willing to lie to cover up its existence, there isn't much someone could do. If people are willing to lie, they will just lie.
Than you counselor.
Glad to help. If I can't do anything else for you, please remember to "rate" my answer. Good luck.
Can I help you with anything else?
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