A person can have their criminal record expunged: if they completed the probation sentence and meet all terms of probation; or by being granted early termination from probation.
Dismissal of a case is the result of an expungement. Persons with an expunged record can answer “No” on any documents, including job applications, that ask if the applicant has ever been convicted of a crime. However, expungement does not remove a conviction from the state of California rap sheet. So it is best to disclose this information before applying for a government job, a job requiring a government certificate, permit or license, or a job requiring a security clearance as the conviction will be discovered.
Expungement of a criminal record will not reinstate the right to possess a firearm unless the charge is reduced to a misdemeanor; and the crime did not involve violence. A court file will still be available to the public and a conviction can be used in future cases as a prior offense to increase the penalty. Expungement of a criminal record gives future employers the sense you’re responsible and made an effort to “do the right thing” after serving a sentence.