Hi there.
I'm in the last step of filing for an employment based green card (filing the 1-485 adjustment of status). I am a citizen of another country. When I was around 18 (over 20+ years ago) I was arrested in my home country for shoplifting. I don't honestly remember much except that I went to court, spoke to the prosecutor and he said sign a paper and you won't have a criminal record.
I then applied for my pictures and finger prints from my arrest to be destroyed which they were so I no longer have a criminal record.
I have stayed out of trouble since and now have a successful career in HR.
The issue is that I now have to reveal this past arrest on my adjustment of status questionnaire and to my employer and from a documentation perspective, I have a police report detailing the arrest, a letter from the police showing my pictures and fingerprints were destroyed, a letter from the courts and the highest police office in my home country stating that i have no criminal record in their system.
For the life of me I cannot find or get any documentation showing what I signed back then so I don't know if it was a conviction or a nonconviction? Do you think I have enough documentation to submit to USCIS and if so how should I approach the explanation of what happened?
Lastly, I am in an atwill state, can my current employer terminate me for this arrest over 20+ years ago even if I have no crimnal record?
Thanks in advance for responding.

