Federal court documents filed in Denver said Donald Hertz of Spokane indicated he was willing to accept the offer with minor modifications. His attorneys didn't immediately return phone messages Wednesday seeking details.

Hertz is accused of calling the Boulder Abortion Clinic in Boulder, Colo., on June 23 and threatening to kill members of Dr. Warren Hern's family. The call came within three weeks of the slaying of Dr. George Tiller, who operated a similar clinic in Wichita, Kan.

Hertz faces charges of making an interstate threat and of violating a law protecting access to reproductive health services.