Per Se usually means a certain blood level of an intoxicant and zero tolerance usually means you can have none in your system, so both of those answers may be true.
It is againast the law to operate a vehicle with marijuana in your system. A police officer must have a valid reason to conduct a stop of a car and must have probable cause to believe that she was under the influence in order to arrest her for DUI and ask for a blood test. Zero tolerance is not a legal phrase and therefore, will not have a bearing on your daughter's case. You should consult an attorney as soon as possible.
**This response does not constitute legal advice and does not establish an attorney-client relationship.
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