In addition to state records, check to see if the facility involved is a Join Commission accredited facility. If so, the Joint Commission will have surveys available to identify potential systemic problems at such a facility. Many of theses are available online from the JCAHO website. When requesting state records for a facility, make sure to request the survey file, the complaint file and the licensure file. Each of these contains different information, which may prove relevant to a case.
You can read more practice tips in my chapter Screening the Nursing Malpractice Case, in a text edited by Patricia Iyer, RN MSN LNCC. More information about Nursing Malpractice, Third Edition, 2007 may be found at here.