Molly D. Castelazo is a research associate and Thomas A. Garrett is a senior economist at the Federal Reserve Bank of St. Louis. They authored this article that analyzes the bad economics of the St. Louis light rail system and includes a devastating chart reflecting how it would have been much more economically prudent to buy a new Toyota Prius for all the light rail riders than to build and maintain the light rail system. The entire article is well worth reading, particularly for Houstonians who have funded a similar boondoggle, and the authors make the following concluding observation:

If light rail is not cost-efficient, nor an effective way to reduce pollution and traffic congestion, nor the least costly means of providing transportation to the poor, why do voters continue to approve new taxes for the construction and expansion of light-rail systems?

One economic reason is that the benefits of light rail are highly concentrated, while the costs are widely dispersed. The direct benefits of a light-rail project can be quite large for a relatively small group of people, such as elected officials, environmental groups, labor organizations, engineering and architectural firms, developers and regional businesses, which often campaign vigorously for the passage of light-rail funding. These groups would benefit from light rail, not from the subsidization of cars and money to all potential riders of light rail.
The costs of light rail, while large in aggregate, are often small when spread over the tax-paying population. (The cost of light rail in St. Louis totals about $6 per taxpayer annually). A large group of taxpayers facing relatively minimal costs can be persuaded to vote for light rail based on benefits shaped by the interested minority, such as helping the poor, reducing congestion and pollution, and fostering development. Even if these benefits are exaggerated and the taxpayer realizes the cost-ineffectiveness of light rail, it is probably not worth the $6 for that person to spend significant time lobbying against light rail.
Proponents of light rail argue that it will create jobs, foster economic development and boost property values. While there is some academic evidence of these benefits, it is important to realize that they are not free to society?light rail is kept afloat by taxpayer-funded subsidies that amount to hundreds of millions of dollars each year.
Concentrated benefits and dispersed costs are one economic reason for the existence of inefficient public projects. The many who stand to lose will lose only a little, whereas the few who stand to gain will gain a lot. Of course, if other public projects exist where overall costs outweigh benefits, then $6 a year per project could add up to quite a hefty boondoggler?s bill.

Dr. Barton Smith, University of Houston professor of economics and director of the UH Institute for Regional Forecasting, is the leading expert on the regional economics of the Houston metropolitan area and has prepared a similar analysis regarding the Houston Metro light rail system.
Alas, I do not expect the Houston Chronicle to address this issue anytime soon. Hat tip to Professor Gordon for the link to this study.