Offense removed? Never. But it only counts as a prior for 10 years.
However, while the general rule is Records are forever, some CA convictions can be 'expunged' from criminal records by proper application and Petition to the court, but ONLY IF there was no felony prison time sentenced whether served or not, and if it was not for certain listed sexual crimes, and if all terms of sentencing and at least one year of probation are completed, and if there are no new charges pending.
Sounds like yours may qualify.
Answered on Aug 24th, 2012 at 10:51 PM