There are many different types of sexual offenses in California which do not required PC 290 registration. These are commonly called Romeo and Juliet laws and deal with two parties who are generally both under age, but they can also be used for people who are generally within three years of each other.
Since you are only just barely 18 and she is 17, absent any other ugly facts, the only real evidence against you is the father who will falsely state he saw you have sex and your statement which the DA will try and use against you. You need to contact a private attorney now to discuss this matter. Please feel free to contact my office. I do the occasional case in San Mateo. Good luck.
Even if you we're to be charged in this case it would be a misdemeanor 261.5. I have never had a client register for this charge. Seek out and speak to an attorney. This case is defensible and should never be filed. You need to do this now though and stop waiting.
Your best situation is to retain an attorney since it may be possible to have the charges rejected by the DA before filing. If not, there are plenty of early solutions but the key is early representation because early contact by your attorney is important in this matter.
Many reputable attorneys offer a free consultation and payment plans. I suggest meeting with at least one soon while the facts are still fresh in your mind.
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I know you already posted this question several days ago, but it seems you added an additional fact, in that you admitted to the father that you had sex with her. Bad move. If you're convicted of a sex offense, you are not going into the military because they won't take you. Unfortunately, none of us can predict the future and we haven't seen any police report. You're probably going to need an attorney but don't post any more details on this site. The cops might be watching.
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