LE using a purple substance from my car to try to say I was involved in an incident. My wife's make-up is the same color.
Admission of evidence at trial can actually be complicated. You need to start with Washington Evidence Rule 104. If the evidence passes the initial test of being admissible, then the question becomes, for what purpose is it offered. Many other evidence rules come into play at this point.
It's hard to answer your specific question without knowing a lot about the facts of the case. Generally, I would say that whether it's the same purple substance in the car and at the scene of the crime would be a question for a jury to decide. The question is more likely, "how much importance should the jury give this evidence?" That is a point for your lawyer to argue to the jury.
Hopefully you are not having this conversation with the police. If you are being investigated for a crime you should understand that the cards are stacked against you. The government has lots of resources and the police can lie and deceive as much as they want. Your only answer to any questions should be ":I demand an attorney." Then use your right to remain silent.
NOT LEGAL ADVICE: All answers are intended to provide information about the law only. Nothing in this answer is intended to be, nor is it, legal advice. NO ATTORNEY-CLIENT RELATIONSHIP: This answer does NOT create an attorney-client relationship. If you want specific legal advice about your situation you must contact your attorney or hire an attorney to represent you.
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