You won't find the case of the trapezoidal windows on the docket of the U.S. Supreme Court — not yet. But it is all about the Supreme Court, and shows how, even at that exalted locale, a construction project can go terribly awry, triggering litigation that never seems to end.

Appeals stemming from a six-year-old dispute over replacement of the court's windows landed this summer with both the U.S. Court of Appeals for the Federal Circuit and the U.S. Court of Federal Claims, and conceivably could make their way to the scene of the crime, so to speak: the Supreme Court itself.

At stake in these and other disputes relating to the court's long-running renovation project are claims for additional compensation totaling more than $15 million — $5 million more than it originally cost to construct the entire court building during the 1930s.

"It's not normal," said Herman Braude of Braude & Margulies in Washington, the lead lawyer suing over the windows. "It should not be this long and drawn out."

The saga begins with Cass Gilbert, the renowned architect of the Supreme Court building, completed in 1935. A stickler for detail, he decided that many of the windows at the court — including the 11-foot-tall windows looking out from justices' chambers — should be slightly trapezoidal. That is, wider at the bottom than at the top. The reason: The tapering would make them look rectangular when viewed from the street.

But that wasn't all. To compensate for their shape on the outside, he made the interior trim of the windows wider at the top than at the bottom, so that from the inside, they would also look rectangular.

"Not at all unusual," said Sharon Irish, an architectural historian at the University of Illinois and an expert on Gilbert's work. Many architects of that period used similar techniques to be sure their buildings were "perspectivally correct," as she put it. At the famed Woolworth Building in New York, also designed by Gilbert, Irish said, "no two windows are the same."

No surprise to an architectural historian, but apparently it was a total surprise to nearly everyone involved in the $75 million modernization project launched a decade ago to bring the building up to date. Nearly $3 million was allotted for the upgrading or replacement of 170 windows, with the goal of making them blastproof in the post-9/11 era. The entire project, supervised by the Architect of the Capitol, was supposed to be finished by 2008.

On the initial blueprints for the project, however, the windows were shown to be rectangular — even though the Architect of the Capitol's office had in its possession original shop drawings from the 1930s showing them as trapezoidal. The rectangular depictions were the ones on which potential contractors based their bids. Some of the drawings bore a warning, however: "All window dimensions to be field verified. Some windows may be tapered."

Grunley Construction Co., experienced in renovation work in government buildings, won the contract in 2004 and subcontracted the window work to Masonry Arts Inc. According to a 2012 ruling by the Contract Appeals Board, neither company field-measured the windows for an entire year. And Braude, the lawyer for Grunley, claims in a brief that the warning "does not tell a contractor that a window is in fact tapered, or warn the contractor to include a contingency in its bid for tapered windows." Under contract law, he said, the company was entitled to rely on the drawings that were part of the bid process.

Eventually, the contractor discovered that "not one single window was rectangular in shape," Braude wrote in a brief. "Trapezoidal windows are much more expensive to fabricate," he added.

But here's the catch: When the measuring was finally done, it was only done on the outside of the windows — not on the inside, which also were trapezoidal, but in a different way. Which is why, when new windows were fabricated, they did not match with the interior trim. Fourteen windows were made before one of them was tested and the error was discovered. They all had to be scrapped. In the 2 1/2 years before the first window was installed, no one had measured the interior side of the windows to find out that they were trapezoidal.

"This came as a complete surprise to everyone associated with the project," wrote Braude, who claims Grunley and Masonry Arts followed standard procedures in preparing and designing the windows. In addition, the company asserts that the government should have shared its "superior knowledge" about the trapezoidal shape of the windows with contractors. The windows have since been manufactured and installed, but Grunley is seeking an additional $757,657 for the extra costs incurred to make the odd-shaped windows. Adrian Bastianelli of the D.C. firm Peckar & Abramson, lawyer for Masonry Arts, declined comment, as did officials from the Supreme Court and the Architect of the Capitol.

Last November, the Contract Appeals Board, part of the Government Account­ability Office, denied Grunley's request, finding that the warning that some windows might be tapered "put Grunley on notice" that it should inquire further and check measurements. "A basic tenet of construction is to 'measure twice, cut once," the appeals board stated. "Yet, Grunley and [Masonry Arts] did not measure the trim at all, despite the fact that they each had a contractual duty to measure." Braude filed an appeal with the federal claims court on August 12, Grunley Construction Co. v. U.S., No. 13-61.

Among other things, Braude claims the trapezoidal shape was undetectable by anyone passing by. He cited the testimony of a government witness who, perhaps unintentionally, paid tribute to Gilbert by stating that the tapering would be invisible to passersby "because the optical illusion works very well." The government's brief denies Grunley's allegations and says the company waived any claims relating to the windows early in the project.

Meanwhile, other disputes were proliferating between Grunley and the Architect of the Capitol over the windows. The parties clashed over whether the windows should be designed to open during a blast or stay closed. There were disagreements over what finish should be used on the window frames. (Justices made the final call on the finish.) The government complained about poor quality and rejected several mockups. Grunley is seeking an extra $2.3 million to compensate for costs and delays related to these matters. The Contract Appeals Board rejected the claim, and an appeal is before the federal circuit. Grunley Construction Co. v. The Architect of the Capitol, No. 2013-1266.

And as the renovation and the bickering continued, justices began complaining about construction noise interrupting their deliberations. Justice Antonin Scalia was once making a presentation to foreign judges when a worker in a nearby room started using a hammer drill. Some of the work was reassigned to the night shift, incurring higher labor costs and delays. Grunley filed a claim over that as well, and Braude said both sides are negotiating over how and whether Grunley will be compensated.

An even larger claim by Grunley — for more than $12 million in additional payments — relates to other delays allegedly caused by project changes and mechanical and electrical problems. That is pending before the Contract Appeals Board.

Meanwhile, the modernization project itself is pretty much completed, although a related but separate landscape project is still going on. Chief Justice John Roberts Jr. has made no secret of his desire to see the project finished. "Things are so dug up in the area, you'd think we were looking for Jimmy Hoffa or something," Roberts told an audience this summer, only half-joking.

In 2007, Justice Anthony Kennedy launched the phrase "trapezoidal window" into the court's lexicon by mentioning it in passing during a budget hearing as a "mistake" that was slowing the project down. But little mention has been made of the litigation. During a 2011 budget hearing, Kennedy said, "There will be claims on both sides, as happens with a long project. Depending on the outcome of those claims, it looks like we're under budget."

Contact Tony Mauro at tmauro@alm.com.