the caucus system is inherently undemocratic. But that is another topic.
abcnews link
The plan was submitted to the Democratic National Committee for approval in August.
The lawsuit charges that changes were made to the agreement since then, however, and that the at-large precincts now unfairly give the casino precincts more weight -- "disingenuously" allocating delegates based on participation instead of based on registered voters, for example
creating a "grossly amplified number of delegates" thus "treating each precinct as if it were a
separate county." (Italics theirs.)
Basically, the lawsuit argues that the way the delegates are distributed is not fair.
There are going to be 10,000 delegates for the 1700 or so normal precincts.
One delegate is given for 50 registered Democrat in a given normal district.
In the special "at large" precincts, one delegate is awarded for every 5 voters that shows up.
For example, if there are 400 Democrats in a precinct and all 400 Democrats show up and vote, the precinct would only award 8 delegates.
In the special "at large" precincts, if 400 people show up, they are awarded 80 delegates.
That is the extreme case and I am not sure how you can resolve this issue since the at large precincts were created from the pool of people that would typically vote in their regular precincts.