A new actor has joined the eigth season of Dexter: Rhys Coiro. Coiro will play a "tough bail jumper that Deb is tracking." So unless Deb has taken up bounty hunting, it sounds like she is still at Miami PD, even after she killed Laguerta at the end of last season.
Coiro has a hefty amount of credits to his name. Recently he had TV roles in Entourage and A Gifted Man. On the feature side, he appeared in 30 Days of Night: Dark Days and the remake of Straw Dogs.
Dexter returns to Showtime early this year, premiering on June 29th at 9pm. It is still up in the air as to whether or not this will be Dexter's last season.
Source: Hollywood Reporter