The next time a Cadillac Escalade obstructs your vision on the highway or a Hummer keeps you waiting 10 minutes to fill up at the gas pump, blame it on the federal government. Keep in mind that in certain circumstances, the U.S. tax code considers these three-ton mamas "capital investments" that stimulate the economy and qualify for tax breaks -- as outsized as they are. For years, Congress has allowed companies that use vehicles for business to count them as tax deductions, and it gave the biggest breaks to trucks and vans weighing more than 6,000 pounds. But when the Jobs and Growth Act passed in May 2003, Congress dramatically expanded the write-offs for 6,000-pound-plus vehicles, which no longer included just trucks and work vehicles, but dozens of suddenly popular luxury sports utility vehicles. As a result, any small business owner, whether a farmer, contractor, attorney, doctor or real estate broker could purchase any of 55 SUVs and trucks priced up to $100,000 and write off the entire purchase price in the first year. That includes everything from the $37,000 Ford Expedition to the $56,000 Cadillac Escalade ESV, the $64,800 Lexus LX470 and the $73,000 Porsche Cayenne. And almost all of the 10,300-pound Hummer H1, the most expensive model at $111,000, can be written off as well. As word spread, the prospect of taking such a large deduction was too appealing for many people to pass up. "I know from talking to my neighbors at the end of last year they needed a tax break," said Curt J. Welker, CPA and managing director with PKF in San Diego. "They ran out and bought them." However, many people misuse the tax break, he said. The vehicles are supposed to be used for business, not for commuting and errands. "You know they're running the kids to soccer and going to the grocer," said Welker. If used less than 100% and more than 50%, the deduction should be pro-rated, he said. For every 100,000 taxpayers in the 35% tax bracket purchasing a $40,000 SUV, this tax incentive is costing the Treasury an estimated $1.4 billion, according to Taxpayers for Common Sense, a Washington, D.C. non-partisan budget watchdog group. "It's absolutely abused," said Keith Ashdown, the group's vice president of policy. "I know families that all they have is business vehicles." Such abuses in the midst of a gas crunch have goaded Congress into action. Several measures have been introduced, some eliminating the tax break altogether, others rolling it back to its previous $25,000 one-year deduction, which is still a pretty good deal. But Ashdown believes the odds are against any action on the matter this election year. So the message to any business owners in the market for a large car, he said, is "Go get it now." Ashdown would like to see all passenger vehicles treated equally without an outrageous loophole for a select few. "There's an incredible amount of good government can do with tax law," he said. "We've always sought legislation that encourages oil independence." Speaking of which, how much does our tax code encourage drivers to save fuel in this era of rising gasoline prices? If you bought a new hybrid vehicle, one that combines an electric motor with a gasoline-powered engine for substantial improvement in miles per gallon performance, between 2001 and 2003, you got a measly tax deduction of $2,000. Starting in 2004, the deduction drops by $500 every year until it disappears. Keep in mind that buyers of the few hybrid models currently on the market have to pay a premium of several thousand dollars just to get a car outfitted with the technology. Dealers are reportedly adding $5,000 to the cost of the popular Prius, a hybrid made by Toyota that retails for $20,000 to $26,000, as waiting lists stretch to six months. The first SUV hybrid, the Ford Escape, will arrive at showrooms later this summer. So here's the choice for the environmentally conscious business owner and taxpayer: Pay $27,000 for the Ford Escape (at least $3,300 more than the non-hybrid version) to get 33 miles per gallon (vs. 21 to 25 mpg for the standard model) and a $1,500 tax deduction, or purchase a $38,000 Ford Expedition getting 17 mpg and take the full $38,000 deduction in this tax year? Let your conscience and your tax bracket be your guide.