Should 11 million mentally ill be locked up? Our view

• There%27s no question that the nation%27s mental health system needs improvement.
• Predicting which person with mental illness will turn into a %22homicidal maniac%22 is difficult or impossible.
• The overwhelming majority of such people are more dangerous to themselves than to anyone else.

The awful mass killings this month by a delusional shooter at Washington's Navy Yard provoked familiar demands to fix the nation's mental health system. Polls show most Americans believe shoring up the system could help stop the carnage.

If only it were that simple.

There's no question that the nation's mental health system needs improvement. Ask almost any parent who has tried to get help for a severely troubled child. The number of psychiatric beds today is less than one-tenth the 500,000 available in the 1950s, and the overburdened, underfunded system fails to treat millions of people with severe mental illness. They and their advocates have long lacked the clout that gets funding for other diseases. If concern over mass shootings helps propel a fix, good.

But the idea that this will end mass shootings is extremely naive — or politically convenient. "If we leave these homicidal maniacs on the street," NRA Executive Vice President Wayne LaPierre said Sunday on NBC's Meet the Press, "they're going to kill. ... They need to be committed."

Getting Navy Yard shooter Aaron Alexis off the streets surely would have saved lives, but the demands by LaPierre — who obviously wants to deflect attention from new restrictions on guns — are far more difficult to meet than he makes them sound.

For one thing, mental health professionals agree that predicting which person with mental illness will turn into a "homicidal maniac" is difficult or impossible. The overwhelming majority of such people are more dangerous to themselves than to anyone else.

Though estimates vary, Rep. Tim Murphy, R-Pa., a psychologist and an advocate for fixing the mental health system, told Congress recently that there are 11 million people with serious mental illness in the U.S., about 2 million of whom aren't being treated, and that people with mental illness commit a thousand homicides a year. That's frightening. But it's also a rate of only 1 in 11,000 people.

Should 11 million people be locked away to prevent those homicides — or even 2 million?

The idea would prove wildly infeasible, legally impossible and hopelessly expensive.

Until the 1970s, snatching people with symptoms off the street and committing them to an institution was permissible. So was keeping them there, no matter their mental state. But a string of court decisions changed the rules by recognizing that the mentally ill have civil rights, and by requiring strong evidence of imminent danger to themselves or others before they can be committed against their will.

This helps explain why police didn't just lock up the Navy Yard shooter when he told them he was hearing voices about a month and half before his rampage. At that time, he had committed no crime, and he posed no apparent danger.

Reducing gun violence will require much more. Mass shootings get most of the news media attention, but people are killed on purpose and by accident by firearms every day in ways that sensible gun restrictions, such as universal background checks, could lessen.

USA TODAY's editorial opinions are decided by its Editorial Board, separate from the news staff. Most editorials are coupled with an opposing view — a unique USA TODAY feature.