I have a B2 visa and spent 5 1/2 months travelling in the US. I returned May 18th. The court date is Sept 25th. Whilst I was there I witnessed an assault. This was a long time ago and I didn't hear much about it until I was forwarded a letter which was basically a summons to court. Now I believe I'm not legally obliged to attend as I'm not an US citizen, however I know the victim personally and would like to help. Also I will be going to Canada around that time so could easily stop there first.
If I return can I say to the border control that I need to attend a court date? As this isn't exactly "tourism" & I don't want to get in trouble.