modeling question

What is the proper modeling approach to the following...

I have a litigation factless fact table that stores a row (1) whenever an insurance claim becomes a suit. Off of the litigation fact there is a defense firm dimension. How do I model for the situation that there can be more than one def firm assigned to suit at the same time?

Either multiple rows in the fact or a bridge between fact and dimension. Since there are no measures, the former is simpler and equally effective.

There is a count of 1 in the fact table to sum the number of events. If I put one row in the fact table for each firm associated with the event I run the risk of over counting. It looks like the bridge table is the way to go can you elaborate on the "bridge" table?

Or you have an event ID (surrogate or otherwise) in the fact and do a count (distinct event_id). This avoids double counting and eliminates the need for a '1' column.