A 56-YEAR-OLD man walked away from the grounds of St. Elizabeths Hospital, where he was under voluntary commitment. Days later, he was found dead under a pile of snow. Another man, committed to the psychiatric institution after being found not guilty by reason of insanity for aggravated assault, is still missing after walking away in December. The two incidents are cause for concern, so we are glad that hospital officials have undertaken a serious review.

The body of Daniel Ellis, who had been in and out of the hospital for the past 30 years, was found Feb. 13 covered with snow on a residential street about two miles from St. Elizabeths. The medical examiner has yet to determine the cause of death. Eric Izlar, age 42 and with a history of violent offenses, is being sought by authorities after walking away from the grounds on Dec. 18. Why the public has been told of the incident only now is one of the questions that officials need to address .

Both men had been granted limited privileges to leave St. Elizabeths and be outside on hospital grounds. It appears, though, that they should have been under some type of staff supervision, so there is a question of whether procedures were followed or protocols need to be fixed.

Phyllis Jones, spokeswoman for the District’s Department of Behavioral Health, said a new policy of checking the identification of people leaving the hospital has been instituted, even as full reviews of the incidents are underway. “We are taking this seriously,” she told us. There are 274 patients housed at St. Elizabeths and, according to Ms. Jones, they sometimes (“about once a month” was her estimate) walk off campus. Most times they are quickly found.

Extending privileges to patients who are judged eligible is an important part of mental health treatment and returning people to the community. There are different levels of privileges, ranging from restrictions and supervision at all times to roaming the hospital grounds without direct supervision. Some patients, by court order, can leave the hospital for outside visits.

Patients who have been judged well enough to handle some freedom should not be kept under lock and key. It’s clear, though, from the tragedy of Mr. Ellis’s death and the concern over Mr. Izlar’s disappearance that better safeguards must be in place to protect both patients and the public.