This is a tricky one. I cannot find any example that specifically lists "court observation." My inclination then is to find something as similar as possible, such as citing a "lecture" or "conversation" or "public address."
According to the Purdue OWL Citation Chart (0ct 2013), "APA provides a method for source documentation that is used in most social sciences courses. The social sciences place emphasis on the date a work was created (or in your case, observed), so most APA citation involves recording the date of a particular work in the physical text. The date is usually placed immediately after the author's name (in your case, "court case") in the "References" page a the end of the paper. Here is an example of a lecture citation in APA:
Here are the basics:
Author, F.M. (publication year) name of lecture. Where and when
Example:
Teplin, L.A. {author last name and first and middle initials} (2013). {date} Early violent deat in delinquent youth {this is the title of the lecture, so in your case it would be the court case} Paper presented at the Annual Meeting of the American Psychology-Law-Society. Los Angeles, CA. {this is where and when the lecture was presented, so in your case, where and when the court case was observed - the lecture title is italizied}
Author, F.M. (Publication Year). Name or title of lecture [file format]. Retrieved from URL
Below is a link to University of Akron's Research Guide for Cases - How to Cite.
If you have additional questions, please contact library staff by emailing: CLUlibrary@callutheran.edu