Herbert and Shirley-Ann Leu were thinking landscaping, not politics, when they built an 85-foot-long concrete wall in their backyard.

But their yard happens to run along the U.S.-Canadian border — a situation that has put the Leus in the middle of a property rights battle, led the Bush administration to fire its own hand-picked border caretaker, and given rise to a legal dispute over the extent of presidential authority.

The Leus, who moved about two years ago from Hawaii to this town in the state's northwestern corner, had just finished building the 4-foot-high wall when they were visited earlier this year by the International Boundary Commission, a joint U.S.-Canadian agency maintains the countries' long, often-unguarded border.

American commissioner Dennis Schornack, a Republican appointed by President Bush, told the Leus their retaining wall stuck about three feet into a 10-foot border buffer zone that had to remain free of obstruction. He said if the Leus didn't tear their wall down, the commission would do it for them — and send them the bill.

The Leus were outraged. They said they had done all their homework before putting in the wall, and none of the local officials who issued building permits ever mentioned such a problem.

So the Leus sued, with help from the Pacific Legal Foundation, a conservative law firm that takes up property rights cases against government regulators and "environmental extremists." The foundation, which also opposes the Endangered Species Act and affirmative action policies, has an annual budget of about $9 million, versus less than $1.5 million for the Boundary Commission.

Schornack began preparing a defense, and resisted when the Justice Department appeared ready to settle with the Leus. If this little wall is allowed to go forward, Schornack argued, what's to stop any other property owner from building an even bigger wall near the border?

Soon enough, Schornack got a one-page fax from the White House: You're fired.

"All he does is try to do his job, and he gets told, `You're fired — because you're trying to do your job,"' said Elliot Feldman, Schornack's lawyer.

Now Schornack, a lifelong Republican and longtime aide to former GOP Michigan Gov. John Engler, has taken his own battle with the Bush administration to federal court.

He argues that he is trying to uphold the treaty he was sworn to protect, while the administration is seeking to remove him for disloyalty — simply because he didn't go along with Justice Department in the Leus' case.

Not only that, but Schornack claims the president cannot fire him, because he works for a binational agency governed by international treaty, not U.S. law. He says the only way to get rid of him is to wait for him to resign, die or become incapacitated.

The U.S. attorney's office in Seattle, which is representing the government in its dispute with Schornack, recently called his claims "breathtaking."

"Mr. Schornack's strained interpretation of the treaty would lead to the absurd result that a commissioner ... receives lifetime tenure and cannot be removed even for malfeasance," government attorneys said in court papers.

The Bush administration has appointed a replacement for Schornack, both on the Boundary Commission and for his second job on the International Joint Commission, which handles boundary waters issues. Schornack was paid about $135,000 a year.

In Blaine, the Leus — he is a 69-year-old retired electrician, while his 72-year-old wife raises Pomeranian showdogs — say all the high-level political controversy seems a little bewildering.

The Leus, who live across from rural British Columbia, say they built the wall to keep their sloping backyard from washing away into the shallow ditch that marks the 49th Parallel, the border with Canada.

Their only motivation, he said, was a nice lawn and a neat patio, with a relaxing view of the neighboring Canadian farm fields and distant, snowy mountains.

Herbert Leu would not discuss his political affiliations.

For now, the wall stands. But while the case winds its way through the courts, the yard remains an unfinished mess of piled dirt, scattered weeds and stacks of lumber because the Leus are waiting to see what happens before they finish landscaping the yard.

"It doesn't make sense — moving a wall just three feet in and it's OK," Leu said. "The whole thing is, we're not putting a wall on the government's property. We're putting it on our property."