If the text shows conspiracy to violate any law it could be a problem.
This looks like more of a suppression problem than a "someone used my phone" problem.
State will argue that it did not obtain the phone illegally.
The drug story would need some corroboration from email recipients. If a person sends emails offering to sell drugs to strangers, it probably won't work. But if police contact the recipients and ask them if its your usual mode of operation and they say yes, then it will be a problem.
Hire an attorney!!! See if the attorney you hire can come up with a strategy to get it back without hurting your position.
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