Panthers' Charles Johnson suspended four games for drug violation

Carolina Panthers defensive end Charles Johnson was suspended four games for violating the NFL's performance-enhancing drug policy, a violation he said in a statement Friday was the result of "an error in judgment" as he dealt with a back injury.
Johnson, in his 11th season, started each of the Panthers' 11 games. He will be eligible to return in Carolina's final regular-season game on Dec. 31 against the Atlanta Falcons.
The specific substance that led to the violation was not disclosed.
"I accept full responsibility," Johnson said in a statement. "I have been recovering from back surgery, dealing with the daily grind of football and mistakenly thought this could help. It was an error in judgment on my part. We have a special group here I wanted to be a part of and felt an obligation to do my part by getting back as soon as possible."
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