By STEPHANIE KLEIN
MyNorthwest.com

Cal Coburn Brown is only hours from lethal injection in Walla Walla and Washington Attorney General Rob McKenna says is confident Brown's last minute appeals will be denied.

Brown confessed to the rape and murder of 22-year-old Holly Washa, of Burien during an interrogation by California authorities over an alleged attack of a woman in that state.

The governor, the Washington State Supreme Court, and the US Supreme Court have all denied Brown stays.

The U.S. Supreme Court and state Supreme Court on Thursday denied separate requests to halt Brown's execution. Brown also asked the U.S. District Court in Seattle to intervene Thursday, repeating a claim that he is incompetent due to mental illness.

"He's throwing a whole bunch of arguments at the wall hoping something will stick," McKenna said. "He has exhausted every possible legal argument, in our view."

Brown argues that his death sentence should be reversed because information related to his mental illness was not adequately considered during sentencing. Brown reportedly suffers from bipolar disorder.

Brown also has filed an appeal to the 9th U.S. Circuit Court of Appeals. He is challenging, among other things, the state's new one-drug system for lethal injection.

McKenna said the courts take each appeal seriously.

"They receive them every time someone is about to be executed in any of the states. They'll have law clerks review the motions and at least one Supreme Court justice will take a look. Once in awhile they will issue a stay based on that kind of motion for an emergency stay," McKenna said.

The attorney general is confident that at this point, Brown will be injected at 12:01am Friday.

"Everything is in place and all the steps have been followed. Holly Washa's family, I'm told, is flying out from Nebraska so they can be present if they choose to and that's what our system of justice calls for. There's no one that I can think of more deserving of this penalty than Brown. This is what the voters of our state believe should be reserved for these kinds of cases."

The Associated Press contributed to this report

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