Because the decision to place him on leave is a personnel matter, it has been referred to the Archdiocese of Seattle.
Archdiocese communications director Greg Magnoni could not be reached for comment Thursday night. Neither could the private Catholic high school's president, Matt Schambari, or athletic director Jerry Zander.
The action followed news that Allison, 41, surrendered his teaching license in Oregon after an investigation in 2009 concluded he engaged in inappropriate conduct with a high school student.
Allison's promotion came after Bill Marsh suddenly resigned as coach earlier this week.
Allison previously served as head football coach at various schools in Oregon, leading Marist Catholic High School of Eugene to a state championship in 2003.
On Wednesday, Zander said the school was aware of the Oregon allegations before hiring Allison, and the school investigated. No criminal allegations were made against him, so the school hired him during the summer, Zander said.
Allison was head football coach and teacher at Gresham High School in 2009 when Oregon's Teacher Standards and Practices Commission started investigating allegations of inappropriate communication with a female student.
In April 2010 he entered a formal stipulation, a legal document acknowledging that evidence showed he violated Oregon teaching rules. He surrendered his teaching license the next month.
The commission found that Allison "communicated inappropriately with a female student via cell phone and text messaging and failed to maintain an appropriate professional relationship with a student."
The stipulation said he also failed to report to school district officials that a student had romantic feelings toward him, and that friends of the female student accused Allison of allegedly having intimate physical contact with the girl.
Allison denied making inappropriate physical contact, although he stipulated to evidence showing an unprofessional "relationship with a student."
Gresham, Ore., police investigated the allegations and did not end up with any criminal charges, Gresham Police Department detective Tony Cobb said Wednesday.
School officials maintain that Allison, who is in the process of trying to get his Oregon teacher's license reinstated, gave it up on the advice of his union legal counsel. He is not required to have one to teach at the private school.
Aaron Swaney covers high school sports for The Herald. Call him at 425-339-3471, follow him on Twitter @swaney_aaron79 or email him at email@example.com.
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