For months now a debate has been raging in economic circles about the long-term unemployed. One group argues that the current unemployment rate, currently at 6.7 percent, is unrepresentative of the labor market because it doesn’t include the millions of long-term unemployed: discouraged workers who have left the labor market. The other side argues that the labor market has segmented—that those with jobs and the short-term unemployed compete for work in one labor market that is tightening, while the long-term unemployed compete in another where jobs are scarce.

A new Brookings Institute paper by Princeton economists Alan B. Krueger, Judd Cramer, and David Cho provides the strongest evidence to date that the latter group is correct. If so, the authors argue, then “a concerted effort will be needed to raise the employment prospects of the long-term unemployed.” In other words, Congress needs to act.

The long-term unemployed can become disconnected from the labor market in two ways. The first is on the labor supply-side. As time goes by, the long-term unemployed become discouraged and their job search intensity drops. Eventually, they drop out of the labor force altogether. On the labor demand side, employers discriminate against the long-term unemployed and pass over their applications out of fear that their skills have atrophied. In either case, the labor market segments.

The Brookings paper says that the longer a person is long-term unemployed, the harder it is for them to find employment. Among workers who report being unemployed for more than 27 weeks between 2008 and 2012, only 11 percent had found steady, full-time employment a year later. Thirty percent were still looking for work and 35 percent had dropped out of the labor force. The remaining 24 percent had found intermittent employment or worked part-time.

Maybe, the authors hypothesized, this only reveals how hard it has been for the long-term unemployed to find a job. As the economy recovers, employers could start hiring them at a quicker pace, indicating that the labor market has not segmented. To check that, they compared the long-term unemployment rate in states with low unemployment with that of ones with high unemployment. They found no evidence that the long-term unemployed have a better chance of finding a job in states with lower unemployment rates. In other words, an improving economy doesn’t help. Even during the late 1990s when the economy was booming, the long-term unemployed still struggled to find work: