Harrison was penalized for roughing the passer for an illegal helmet-to-helmet hit against Cleveland Browns quarterback Colt McCoy, "a defenseless quarterback," according to the league.
Harrison was fined four times for illegal hits against quarterbacks in 2009 and 2010 and twice for unnecessary roughness for a total of six fines during that time.
"Players who were fined for violations in 2009 or 2010, and whose fines were either partially or fully upheld, will be considered second and/or repeat offenders under this policy," the NFL stated.
Under NFL rules, Harrison can't return to the facility or practice until his reinstatement on Dec. 20.
Harrison can appeal the suspension under an expedited hearing this week before the weekend to be heard by either Art Shell or Ted Cottrell.
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James Harrison suspended for one game
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