If I invite you to my home for an evening of TV viewing, don't forget to bring your glasses: I'm one of those weird people who watch television with the closed captions turned on.

I'm not hard of hearing; I just prefer a belt-and-suspenders approach to TV comprehension. The habit started when I missed dialogue on an episode of "The Wire," and it continued when my girlfriend wanted an assist understanding accents in shows from my native England. It has become so ingrained that the first thing I do when checking into a hotel room is reach for the TV remote control and search for the "CC" button.

But as TV viewers are increasingly liberated from the broadcast schedule -- thanks not only to DVR-driven time-shifting but also to devices that stream thousands of movies and shows from Netflix and Hulu Plus direct to our sets whenever the mood strikes -- the technology for closed captions hasn't kept up. This is a minor annoyance for people like me who want a little extra help understanding accents. It's a much more serious problem for those who are hard of hearing.

That makes it a legal problem, as well.

Closed captions -- called "closed" because viewers can choose to turn them on or off, whereas "open captions" are visible at all times -- were developed in the 1970s. They were created to make television accessible to deaf viewers who cannot pick up any audio cues, and so they go well beyond the transcribed dialogue you might find on a foreign movie's subtitles. They also indicate background noises, note who's speaking at times when it isn't obvious, and sometimes describe musical cues. (The "30 Rock" theme, for example, is "exciting jazz music.")

Since 1990, televisions with screens larger than 13 inches have been required to contain the circuitry necessary to display captions, and since 2006, all new English-language video programming, including live broadcasts (with a few exemptions), must contain captions. In many markets, broadcasters can use the "electronic newsroom technique," in which news-broadcast teleprompter scripts are used as captions, which means that deaf viewers miss live location reports, breaking news bulletins and unscripted badinage between reporters. But in the top 25 TV markets, broadcasters must provide full real-time captions for all live transmissions.

Broadcasters take the legal requirements seriously in part because the National Association of the Deaf, an effective lobbying group, encourages its members to complain to the FCC whenever captions are absent or unreliable.

One company that many Deaf Association members have complained about is Netflix. In June 2010, the association sued Netflix, claiming its failure to provide closed captioning on its "Watch Instantly" streaming service violates the Americans With Disabilities Act (ADA). A judge recently refused to toss out the lawsuit, rejecting Netflix's claim that the ADA doesn't apply to Internet-only businesses or to services that people use at home rather than in public places.

In February 2011, Netflix said "subtitles" were available on 3,500 TV episodes and movies, which together account for roughly 30 percent of the site's available viewing. The company said it expected to reach 80 percent of viewing coverage by the end of 2011 -- but it doesn't appear to have updated subscribers on its progress toward this goal in the 17 months since.

The problem is that the subtitles are visible only on computers and on devices such as phones and tablets and not if you stream Netflix output to your television via a device such as a Roku player. The issue is technical, the company claims. It's the "closed" part of the name -- the ability to choose whether the captions are visible -- that makes it tricky.

Computers -- and devices like iPhones and iPads -- can handle the complex "encoding" software, whereas smart TVs and set-top boxes may or may not have the processing power to do so. (Hulu users are in the same fix. Closed captions are available on "some" of its shows for online viewing and via a limited number of Internet-connected devices.)

The technical challenges aren't trivial, and at least until the Deaf Association's lawsuit is decided -- which could be a ways down the road -- Netflix doesn't have much obvious incentive to invest time and money in solving them. Manufacturers of televisions and set-top boxes, competing in a market with increasingly narrow margins, have even less.

The Deaf Association lawsuit might be just the carrot -- or, more accurately, the stick -- that the company needs, especially if that lawsuit starts to get more attention.