Should i sue this company???

i went to apply for this aid position for a VERY WELL KNOW cerebral palsy organization, they did drug, and backround check, back in 99 i got arrested for petty larceny, i hired a lawyer, case was reduced to disorderly conduct, it shows up in my record as disorderly conduct, not petty larceny, i have worked for this company before, after this all happend, i was offered the job by the director of the company, but when i went in to fill alll the paperwork i told the women upfront what had happend in the past, i told her it will not show up,(i have done my own backround check and nothing shows up,) she started lookin at me funny, and said she had to talk it over with her supervisor, 2 weeks later im still waiting for the call, so i called myself, they told me that SOMETHING had come up on my record and they could not hire me! i asked her what did u find, she said I DONT KNOW, but there was something. I know that nothing showed up but, she discriminated me just by what i told her.