Lost Judgment

Complete 10 of the 42 available side cases (DLC side cases don't count).

Side cases open up in Chapter 3, once you have the 'Buzz Researcher' app (although there are a few story-related ones before this). They appear on your map as blue folders icons.

Some are started from the noticeboard in your agency HQ, so check that occasionally.

There are 42 in total so you should get this through normal play. If you do them as they become available, you can get this as early as Chapter 3, while still in Yokohama.

The first 10 I got were:

1. Skateboard Detective vs. The Reseller - story-related, Chapter 1
2. The Falling Man - story-related, Chapter 3. This is the case that opens the rest up.
3. Let the Drones Fly! - Chapter 3, near the Batting Center
4. Where is the Time Capsule? - Chapter 3, Seiryo High courtyard
5. Extracting the Past - Chapter 3 - story-related, Chapter 3
6. The SRC's Hunt for the Truth - Chapter 3, Seiryo High (night), get keyword 'UFO'
7. Paradise VR Unlocked! - Chapter 3, by Sesil Café
8. Paradise VR Upgraded! - Chapter 3, by Sesil Café (needs a lot of Play Passes)
9. The Forbidden Taste - Chapter 3, from HQ noticeboard
10. Extracting the Truth - Chapter 3, Iyama's Extract Shop

For help with finding and completing side cases, see CyricZ's super-useful guide on GameFAQs:
https://gamefaqs.gamespot.com/ps4/320117-lost-judgment/faqs/...