Unless your theft charge was dropped for lack of probable cause, you were acquitted by a jury or judge after jeopardy attached, or you have received a pardon from the governor, it's not expungible. If you have received probation or deferred adjudication, even if completed successfully, its still not expungible. However, in the case of a successfully completed deferred adjudication you may seek a "petition for nondisclosure", which would seal your records from the eyes of any private agencies or private employers, but not law enforcement or state agencies. For example, a state licensing committee, such as the board of medical examiners or the state bar of Texas, or a state hospital, could view the theft charge, but not Hugh Heffner, assuming you wanted to work for him.
The answer above is why attorneys from other states shouldn't answer questions where they're not licensed to practice. There is no "petition for nondisclosure" in California.
Specifically built into the "expungement" section [Penal Code section 1203.4(b)] is an exclusion of infractions from being able to be "expunged".
That is scheduled to change in 2011 where you can apply for a dismissal under 1203.4 after one year.
You may still not be 100% in the clear however. Although this may exempt you from having to disclose in (if expunged) on a grad school application, it may still need to be disclosed for your professional licensing application. You may want to seek an in-person consultation with an attorney that specifically handles licensing issues.
Texas is Texas.
California's applications for professional and occupational licenses ALL ask whether the applicant has ever been convicted of a crime. All California applications further expressly state that ALL prior criminal convictions must be disclosed, even misdemeanors, even expunged convictions, even old convictions, even convictions based on a plea of nolo contendere, even unsealed juvenile convictions, and even all other convictions for which one can articulate a theory as to how the conviction isn't a conviction.
The plain and inescapable fact is that ALL convictions MUST be disclosed on any California licensing application.
The California licensing applications also ask for a "full" statement of the facts and circumstances underlying each conviction. This is where a short and inexpensive consultation with an experienced licensing attorney may be highly cost-effective. An attorney can assist you in crafting a statement that best "manages" the prior conviction information. There are a number of statutes in California which specify facts and circumstances that the State licensing agencies must take into account in assessing whether a prior criminal conviction will be grounds for denial or restriction of a license. An attorney can assist you in crafting your "full" statement so as to maximize the statutory factors of mitigation, minimize the "relatedness" of the prior conviction to the duties and functions of a licensee, and demonstrate a credible and persuasive presumption of rehabilitation completed. A well-crafted "full" statement of the facts and circumstances underlying a prior conviction is the single most important step in the licensing application process for those who have criminal history issues. Once filed, the disclosure of prior convictions and the "full" statement of facts and underlying circumstances are a permanent part of the license application. Any subsequent appeals of a denial of a license will necessarily be limited by the boundaries and contents of the "full" statement.
A final caution: if you fail to disclose a prior criminal conviction (even those which are subject to the theories of wishful thinking set forth above), the State WILL FIND OUT based on the fingerprint check. Then, the license application will be denied on the additional independent grounds of filing a false application, failing to disclose required information, and attempting to procure a license fraudulently. These are all illegal and dishonest acts which, in the view of the State, are inconsistent with the proper and competent performance of the privileges and duties under the applied for license.
DISCLOSE, DISCLOSE, DISCLOSE.