The first step should be to contact a criminal defense attorney that handles expunctions. Make an appointment, most offer a free consultation.
The Second step is to determine whether you are even eligible. It will depend on the disposition of the case. Was it dismissed? Was it dismissed because of a pre-trial diversion? If it was dismissed without going through a pre-trial diversion, then you should be eligible now. If you went through a pre-trial diversion, the State’s contract that you signed contains a clause that you will not seek an expunction until 2 years after you complete the pre-trial diversion. If the appropriate time has passed, then you should be eligible now, as long as you did not commit any other crimes other than minor traffic offenses.
Third, assuming you are eligible, you must prepare and file a petition for expungment / expunction in accordance with chapter 55 of the Texas Code of Criminal Procedure. The filing fee in Harris County is approximately $300.00. I suggest that you hire an attorney. Call around because the price for this service varies from $500 dollars to a few thousand. Good luck to you.
Legal disclaimer: My answers are only intended as general legal advice based on my experience. They are not intended to be a binding legal opinion nor to create an attorney-client relationship.
If you plead guilty and did any jail time or received "time served" or were put on regular probation, this case cannot be expunged. If you received deferred adjudication, however, you can find some relief if you completed the community supervision satisfactorily. Find an attorney to petition the court to order that the case not be disclosed to anyone other than law enforcement or government agencies. Feel free to call.
As long as it was dismissed you can go ahead and file a motion for extinction now. If you received deferred adjudication and successfully completed it, you are eligible for a petition for non-disclosure. Otherwise any other conviction even if it was probation will not entitle you to an extinction. I see your located in Houston, if you need any more assistance in this give my office a call and I can set up a free case evaluation to go over the case with you.
If you find my advice helpful or would like me to represent you on a criminal matter. Feel free to call my office at 281-947-2007. If you are looking for additional information my website may be of use: www.maverickraylaw.com. If you are in the Houston area feel free to stop by my office anytime: 1419 Franklin St. Houston, TX 77002.