Because of changes in Ohio mental health legislation in 1978, mentally disordered criminal offenders can now be turned over to the civil probate court for civil commitment procedures. In part because many officials in the civil hospital system fear the admission of dangerous criminals into their hospitals, the authors conducted a statewide research project to compare civil and criminal patients on demographic, diagnostic, and behavioral variables. There were no differences between the two groups on some indices of dangerousness, but on other variables the two groups differed. Sometimes it was not the forensic but the civil patients who appeared more threatening. In all, the forensic patients did not constitute a unique class of patients who are clearly and categorically more dangerous than civil patients. The findings suggest a more open-door policy toward forensic clients in the civil mental health system.