What's the legal definition of blindness?

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March 14 2008 3:23 PM

Legally Blind?

How bad is David Paterson's vision?

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David Paterson. Click image to expand.
David Paterson

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New York Gov. Eliot Spitzer announced on Wednesday that he would step down from office effective March 17. The man who will replace him, Lt. Gov. David Paterson, will be the first legally blind governor in U. S. history. What does it mean to be legally blind?


Your vision is 20/200 or worse in your best eye, even with corrective lenses or surgery. According to the federal statute that defines legal blindness, a person also merits the designation if he or she suffers from severe tunnel vision, with a visual field that measures at most 20 degrees in diameter. (An average person can see about 160 degrees without rotating his head.) In either case, however, the blind person must suffer that impairment for at least 12 continuous months. The government also won't recognize any disability that resulted from the commission of a felony or the ensuing prison term. So if Spitzer ends up in the slammer for, say, illegal structuring and then has his eyes gouged out in a prison fight, he may not meet the federal definition for legal blindness.

A blind person may also be left off the government rolls if the source of his impairment was central as opposed to peripheral. That is to say, someone who was rendered virtually blind as a result of brain damage—someone whose cortex couldn't make sense of a visual scene, for example—would not be considered "legally blind," so long as his eyeballs themselves were functioning normally.

The strict definition now on the books wasn't codified until the 1960s, although federal protection for the blind began with the Social Security Act in 1935. The act required that each state establish an agency to provide financial assistance to people with debilitating vision impairments. The legally blind are also protected under the Americans With Disabilities Act, which ensures that they be accommodated in the workplace. Since World War II, the legally blind have also been allowed a special deduction (or, at one point, an exemption) on their federal income taxes. (Some states give additional tax benefits.)

In some states, legally blind people are prohibited from operating automobiles; in others, they may obtain a special driver's license with restrictions on when and where it can be used. * In Texas, you can get a hunting license no matter what your vision (although to use it, you'll need an assistant), and many states offer free lifetime fishing licenses to the legally blind.

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Correction, Oct. 27, 2009: The article originally stated that legally blind people can never obtain a driver's license. In most states, they can apply for a restricted driver's license, as long as their visual acuity exceeds a legal limit with the aid of a bioptic telescopic device.(Return to the corrected sentence.)



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