The Eighth U.S. Circuit Court of Appeals on Friday upheld $45,451 in sanctions against Minneapolis foreclosure attorney William Butler, under fire from local federal judges who have repeatedly sanctioned him.

It was the second time in two days that the Eighth Circuit rejected claims made by Butler, who is under investigation by the local federal judiciary.

In Friday's ruling, the three-judge appeals panel said, "It is entirely improper and frivolous to continue to file baseless claims with superfluity. The district court was well within its discretion to impose sanctions."

The ruling upheld a decision by U.S. District Judge Donovan Frank in a lawsuit Butler brought against the Bank of America and other banking entities.

Last week, Michael Davis, chief federal judge in Minnesota, appointed retired chief judge James Rosenbaum to investigate Butler for possible discipline. Davis cited nine cases since 2011 in which Butler has been sanctioned by local federal judges, all for bringing frivolous claims that they said had been unanimously rejected by federal judges in Minnesota, the Eighth Circuit, and by the Minnesota Supreme Court.

The judges have accused Butler of tying up the court system. The sanctions total $323,307, according to the Star Tribune's calculations, including $45,451, imposed by Frank on Nov. 30, 2012.

Butler's theories over "quiet title law," establishing the legal ownership of real estate, have been invalidated, Frank wrote. He said Butler had not alleged facts that would show that any of the banks "was not the record owner of any mortgage at the time it initiated any foreclosure by advertisements."

On his website and in an earler interview, Butler defended his decision not to pay the sanctions, insisting that his position challenging the legality of foreclosures is correct, that judicial decisions are erroneous, and he will ultimately prevail.

Asked to comment, Butler e-mailed this statement:

"I am disturbed that the 8th Circuit, like the local district court, continues to refuse to acknowledge the very clear 150-year history of Minnesota quiet title law that places the burden of proof squarely on the banks. On my website your readers can see what the law actually is and also that the Federal Judicial Center has determined that federal courts are dismissing 92 percent of plaintiffs' claims without ever letting them get to first base. Instead of following the rule of law, they attack and sanction the messenger."

Butler is also being investigated by the state Lawyers Professional Responsibility Board. U.S. District Judge Patrick Schiltz, who imposed $79,766 in sanctions, asked the board for that investigation.

Joseph Daly, emeritus professor at Hamline University School of Law, said it is likely that Butler will be suspended.

"He's appeared before all these judges and they have told him these are frivolous lawsuits and the rules of professional responsibility prohibit us from filing frivolous law suits," Daly said.