The same as impanel, empanel means to choose and seat the jury for a case. The basic steps to empanelling a jury include:
1) Randomly gathering together a group of prospective jurors
2) Choosing which individuals will serve on the jury
3) Allowing the prospective jurors to give reasons why they should not serve on the jury
4) Allowing the prosecution and defense to use their challenges to dismiss prospective jurors
5) Swearing in the jurors and alternative jurors.
See also, Voir Dire and Jury Selection.