Because the plea bargain is what would still leave him a registered sex offender.
Judge orders Genarlow Wilson freed The Atlanta Journal-Constitution | 06/11/07
The attorney general's office disclosed that as recently as this past weekend Douglas County offered Wilson's attorneys a plea deal that would have allowed Wilson to avoid a criminal record and inclusion on the sex offender registry once his sentence had been completed. The plea deal would have also allowed Wilson to serve a "substantially shorter" prison sentence, possibly leading to his "release based upon time already served."
Wilson, through his attorneys, refused those offers.