Legal Question in Criminal Law in California

Without reading the question that is posed on your application, it is hard to answer your question. When in doubt, be honest and disclose it. Dishonesty is a great way to disqualify yourself. At least by being candid, you put the onus on the military to decide if the citation is too remote to disqualify you.

If there is no record of conviction in the court system, you need to seek a copy of your FBI/DOJ record to see if it shows there. If not, you are free to choose whether to voluntarily disclose the unknown conviction. You should also promptly seek to 'seal and destroy' your juvenile record so it is no longer accessible. If serious about hiring counsel to help in this, and if this is in SoCal courts, feel free to contact me.

Are you sure it is even a "conviction?" I agree with Mr. Hill, and I do suggest you speak to an attorney to determine what the status of the previous charge is and what information the military exactly seeks.