AUSTIN, Texas -- A couple of statewide Democratic candidates say a loophole in Texas tax law allows commercial property owners to save bundles, while homeowners pay the full way, which ultimately causes local governments to lose out on billions of dollars in property tax revenue

Lt. Governor candidate Mike Collier and Andrew White, who's running for governor, both claim local governments are losing out on about $5 billion each year because of a law meant to ensure Texans pay similar property taxes as their neighbors. 

"It's been abused by commercial interests to bring down their property values," said Dick Lavine with the left-leaning Center for Public Policy Priorities.

Lavine said the law unfairly allows commercial property owners to liken their buidlings to less expensive ones across the state, pushing their property taxes lower.  

"And you start to spiral down, so commercial properties aren't on for their full market value anymore," Lavine said.   

Those in favor of reforming the Equal and Uniform law say the extra billions in unpaid property taxes could go toward Texas' public school system. But Dale Craymer of the Texas Taxpayers and Research Association said the law continues to be an important protection for property owners. 

"What we're talking about eliminating is a right that all property owners have. Not just commercial property owners, but also home owners. And we have to tread very carefully when we talk about scaling back rights," Craymer said. 

While Cramer said the law has been vague in the past, lawmakers made changes in 2015. 

"To tighten up what constitutes a comparable property, so we're still in the process of sort of seeing whether those changes were sufficient," Craymer  said.