LITTLE ROCK (AP) - Lawyers for four Arkansas death-row inmates are urging a federal judge to allow a challenge to the state's lethal injection method to be heard after the U.S. Supreme Court found a similar method used in Kentucky to be constitutional.

Lawyers for Don William Davis, Jack Harold Jones Jr., Terrick Nooner and Frank Williams Jr. filed their claim Wednesday in U.S. District Court. A filing by federal public defender Julie Brain alleges Arkansas' lethal injection procedure is "so dangerous and inadequate that, even when followed as directed, it has resulted and will continue to result in the infliction of excruciating, and entirely unnecessary, pain and torture."

Williams, 41, faces a Sept. 9 execution date set by Gov. Mike Beebe. If it is carried out, Williams would be the first inmate put to death in Arkansas since 2005.

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