An ex-lawmaker's challenge to stop the state from spending taxpayer money on a $90 million Senate office complex is now in the hands of a Ramsey County Judge.

Wednesday marked the first round of courtroom arguments since former Rep. Jim Knoblach sued the state over the controversial project, which was rolled into an omnibus tax bill as the 2013 legislative session drew to a close. The move was unusual for construction projects, which are usually part of the bonding bill.

Knoblach's attorney, Erick Kaardal, argued that including such a project violates state rules that prohibit a law from embracing more than once subject. Spending taxpayer money on a project wholly unrelated to taxes is a clear violation of the law, he said.

"This was Governor Dayton's marquee tax bill," Kaardal said, ticking off the multiple taxes addressed in the bill, and how the funding for the construction project stood out. "With tax bills we don't expect spending to be in them. This is a prototypical case of legislative logrolling."

The $63 million building and adjoining $27 million parking facilities drew fire from Republicans, who protested as the Senate rules committee voted last week to move forward with construction.. Democrats said that the building's construction is directly linked to the ongoing renovation of the Minnesota State Capitol, which will require additional office space as tenants are displaced during the project.

Kaardal argued that such projects would normally be funded through a bonding bill, which requires a 60 percent majority of lawmakers for approval. In this case, rolling it into the tax bill required only a simple majority.

"It's possible this could be the start of something bad," Kaardal said, adding that the drive was spearheaded by Senate Majority leader Tom Bakk, DFL-Cook. "You have Sen. Bakk, a very important official, doing this. If the state wins, this is a new precedent and we don't want this to happen again."

Assistant Minnesota Attorney General John Garry argued that not only does the state have revenue-raising authority that made the project's inclusion into the tax bill relevant, but Knoblach's legal challenge should be thrown out altogether because he cannot bring a lawsuit challenging the project simply because he is a taxpayer.

"If you allow someone to challenge the construction on the basis of being a taxpayer, that means any plaintiff can challenge any legislation regardless of whether he has suffered any injury," Garry said.

"If a taxpayer does not have standing to challenge the constitutionality of legislation, does anybody?" District Judge Lezlie Marek countered.

Garry said there is no prior case law that allows a plaintiff to have standing simply because they are a taxpayer.

"That is the status quo," he said.

Marek, who has 90 days to issue a decision, said she would rule as soon as possible. Afterward, Knoblach said the legal argument that he wouldn't be able to bring such a court challenge is a premise he finds hard to believe.

"If I can't do it in a case like this, how can a suit be brought?" he said.

Knoblach said that if the judge rules that the Senate majority's actions were legal in rolling the project into the tax bill, it would render separate committees moot when it comes to lawmaking. He's uncertain at this point how far he'll take the case should the judge rule against him.

"That's bad for transparency to the public, bad for legislators knowing what they're voting on, and that's the way this could go," he said.