First, need to qualify for a public defender. If judge does not think person qualifies, then will have to retain an attorney. Generally speaking, private attorneys have more time to dedicate to the case. But public defenders are very capable to handle these types of cases. By the way, what county is the case pending in?
Generally speaking you are better of choosing your own attorney than having one appointed. The court will only appoint the PD if the judge agrees that the defendant cannot afford his own counsel. Your brief scenario raises a question about the existence of probable cause to search a passenger during a traffic stop. The defendant should consult more than one experienced criminal defense attorney. Most of us provide free consultations. www.galivanlaw.net
I believe I just answered this question so it must be posted twice. If you are eligible for a PD ask for one. You won't have to spend money and PD are very good attorneys. Hire an attorney if you decide you want to and/or if you can't have a PD.
You asked this question twice.
Public defenders are very experienced criminal defense attorneys. However, because of their high caseloads, they are unable to give each client a lot of personal attention. Not everyone qualifies for a PD. The defendant must be financially unable to afford private counsel.
Private defense attorneys obviously cost more than PDs. Their experience varies. They are better able to give more attention to each client and to delve deeper into investigations when necessary due to their less limited budget.
If you can afford to help your son, a private attorney might be better for him, given the circumstances you describe. This case very possibly could go to trial. There are many good criminal defense attorneys near you. If you are unable to receive referrals from friends or family, feel free to contact me and I can furnish some names.