Anyone who commits a crime in a municipality directly under the Central Government will be sent back to the local area to serve his sentence.
The case-handling organs in Beijing are easy to talk about, unlike many accidents in other places.
Suggestion: Call the Beijing Reporting Center. If it is not a major case, you should get a direct reply. If a major case shows that it is beneficial to suggest relatives of the case-handling organ to intervene, the case-handling organ should give you what you want.