An anti-tax group is suing state lawmakers for illegal spending over the last 28 years.

The group called Citizens Lowering Our Unfair Taxes or CLOUT filed the suit in Travis County on Wednesday naming legislative leaders as defendants.

The suit contends lawmakers are using inflated budget numbers to overspend, they believe that's leading to Texans being overtaxed.

Families are getting over-charged an average of $1,300 a year, CLOUT said.

"If we don't start fixing today where are we going to be 20 years from now? We figure the estimate is $26,000 per household in the state of Texas [from] 1980 to 2000," Edd Hendee of CLOUT said.

The lawsuit is based on a 1978 voter-approved Texas Constitution amendment, which forces the legislature to increase spending based on an estimated growth rate.

In the last few years state government has increased spending 6 percent a year.