Hi, in Oct. 1990 i was convicted of Possession of Marijuana for sale (11359 H&S) and received 3 years probation and no jail time.

Since then I've received my Dept. of California Real Estate License and California Locksmith Liccense from Bureau of Security and Investigative Services with no problems. Also was hired by the City of San Diego with no problems either. Its the only problem i've had with the law in my 44 years.

Is it possible to have this expunged? And could i do this myself?
Thanks for your help