PARTY table which contains information about the parties involved – unique VEH_ID field. A common way to work with data of this structure is to create a party-level table or a victim-level table that has data from all its parents joined to each row. For example, if you plan to do analyses at the victim-level, you can start with a VICTIM table and join in values from corresponding PARTY and CRASH tables. Please refer to this link for the related Victim tables. Please refer to this link for the related SWITRS collision data. For more references on joining this table to SWITRS collisions, go to this link at LA County GIS Portal.