Baltimore City was dismissed from the suit due to sovereign immunity and Douglas settled their aspect of the case.
The family intends to press on with the case against the city, hoping to revive the previously dismissed aspects of the case.
Sovereign immunity is the concept that governmental entities can proscribe when they may and may not be sued. It is literally a by-product of a long-ago era when the English kings or sovereigns, gradually permitted their subjects some redress for certain wrongs committed against them by their king (or queen).
For more see: http://www.baltimoresun.com/news/maryland/bs-md-green-park-lawsuit-20100928,0,391013.story