Your question is extremely broad. Defenses are formulated based on the particular facts of the case and after all evidence including police reports, lab reports, photos, statements and recordings have been reviewed. There are inumerable possible defenses depending on the discover provided by the prosecutor.
Certainly, one ofthe first issues that may be reviewed is whether the officer had requisite reasonable supicion to stop the vehicle. To have reasonable suspicion, the stop cannot be based on an arbirtrary notion or caprice, but, instead on an articulable suspicion or particularized illegal activity. Obviously, the question here is whether the tail light complied with applicable law. In most states, a tail light cannot have white showing since it creates a danger that a vehicle behind will see the light and believe it is a vehicle traveling in his or her direction.
A second issue is whether the officer had requisite probable cause to search the vehicle. The officer's training and experience in recognizing drugs would be a critical to the case and may be challenged. If the probable cause for the search is lacking, the evidence may be suppressed.
Possession of the contraband is also an issue that can be challenged. That means challenging whether the person charged was in actual or constructive control of the contraband seized.
In most cases, if your son has a clean record, he may be able to negotiate a stay of prosecution. That means the case is put on hold for a probationary period, usually one year. If he abides by all conditions which may include remaining law abiiding and/or attending a drug treatment class or program, the charges may be dismissed.
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