> Wouldn't they just... buy drugs and stick them in the car? Maybe they want to create too many false positives deliberately, or maybe they do it just because

> Wouldn't they just... buy drugs and stick them in the car? Maybe they want to create too many false positives deliberately, or maybe they do it just because they want to see if and how synthesizing such a chemical can be done. When putting pictures on someone's phone or computer, there are ways to add false positives as well as maybe doing false negatives sometimes (e.g. by encrypting the picture or using an uncommon file format so that it must be converted, or using complicated HTML/JS/CSS to render it instead of just a picture file). Also, if someone has the picture or drug or whatever to find if it is what they are, can you accuse them (maybe they are the police) of liking pictures and drugs, too?