A man we know once told us that the most harrowing experience of his life was the evening when a loud, laugh-filled pillow fight with his 7-year-old daughter was interrupted by a knock on the door by two grim-faced police officers who suspected him of beating his child.

The Denton State School has just heard such a knock, not from a couple of uniformed patrolmen but from the federal Justice Department’s civil rights division. The Justice Department intends to investigate the school apparently for possible negligence or abuse of one or more of the approximately 600 minor and adult clients who live there because of mental or physical disabilities.

The front-page article in Thursday’s paper said the Justice Department had received “dozens” of complaints alleging abuse or neglect of clients at the school since 2002, when a young adult male client was severely beaten by an employee who had been abusing drugs at work. Officials at the state Department on Aging and Disability Services, which oversees Texas’ State Schools, said it would cooperate with the investigation.

This is not the first time that one of Texas’ State Schools has been investigated for possible abuses. Justice Department officials spent about 18 months at the Lubbock State School beginning in 2005. The results of that investigation were disturbing: There had been 18 client deaths at the school in an 18-month period, 66 percent of the clients there had been injured by other clients, and there were many incidents of improperly restrained or sedated residents.

It is hard for us to know what to think about the pending investigation. The State School is an institution that is dear to Denton’s heart but far from its sight. We admire the school’s mission, and are proud to call it a part of our community, but too many of us are content to admire it in the abstract and leave the hands-on experience to the professional staff and a few dedicated volunteers. Most of us are aware that the administration of such a facility presents tremendous problems for those who run it. The financial constraints the school is forced to operate under are common knowledge to everyone who pays even the smallest attention to its operations.

Most of us know, too, at some level, that opportunities for abuse abound at such institutions, where the needs of clients are complex and not always pleasant to deal with, and pressures on personnel are unrelenting.

Our friend — the one whose pillow fight was interrupted by the police when the delighted shrieks of his daughter alarmed the neighbors — remembers the experience with a mixture of fear and appreciation — fear at his own helplessness at the hands of the polite but suspicious police officers; appreciation for their professionalism and obvious concern for the welfare and safety of a child.

Our feelings are not unlike his at this point. Our hopes and natural sympathies are with our neighbors who run the Denton State School, but our first concern is for the welfare of those who are in their care.

There is a natural tendency to hope that this investigation will be short and sweet, but we must fight that tendency. We hope instead that it is thorough and uncompromising; the stakes are too high for anything else.