|First appearance||"The Routine" (episode 1.01)|
|Last appearance||"Straight Life" (episode 1.05)|
|Reason/Cause||Fired for drug smuggling|
|Episode Count||5 Episodes|
|Portrayed by||Steve Ryan|
A correctional officer, he is a friend of Cyril O'Reily on the outside. When Cyril's brother, Ryan, is imprisoned, Healy strikes a deal with O'Reily in that he'd provide O'Reily with protection if O'Reily dealt heroin on his behalf. As a result, Healy and O'Reily form a drug running operation in Oz, which works out fine until Nino Schibetta discovers it and forces O'Reily to dismantle it.
A disgruntled and corrupt officer, Healy has a very low opinion of both the inmates and unit manager Tim McManus. He helps O'Reily dispose of Jefferson Keane by videotaping and framing him for the killing of Julio Martinez, which lands Keane on death row. Bob Rebadow attempts to inquiry about the videotape that he and the other COs were using to frame Keane, but Healy destroys the tape, then confronts Rebadow personally and warns him to stop asking about it.
Healy and O'Reily's main partnership is through their drug running operation. Healy trafficking heroin into Oz, and O'Reily selling it to the prisoners in Em City. Their operation competes in the drug trade with the Homeboys and, more importantly, Nino Schibetta. Schibetta eventually discovers Healy and O'Reily's side business when it starts to cut into his profits. He instructs O'Reily to betray Healy in exchange for partnership in his operation. O'Reily takes Schibetta's deal and gets Ronald Poklewaldt to inform the prison officials about the upcoming drug deal that Healy was having with him.
At the deal, Healy is busted and arrested for drug trafficking, then fired from Oz by Warden Glynn. O'Reily, however, refuses to testify against Healy in court. O'Reily also informs Officer Hunt that Poklewaldt was the one who ratted out Healy. Hunt and some other COs then take revenge on Poklewaldt by beating and hospitalising him.
- Julio Martinez: Killed in self-defense by Jefferson Keane. Arranged for him to kill Keane but backfired. (1997)
- Jefferson Keane: Executed by lethal injection after being found guilty of the murder of Julio Martinez. (1997)
Warden Leo Glynn - Tim McManus - Sister Peter Marie Reimondo - Gloria Nathan - Father Ray Mukada - Martin Querns - Lenny Burrano - Dr. Tariq Faraj - Diane Wittlesey - Sean Murphy - Claire Howell - Clayton Hughes - Karl Metzger - Andrea Phelan - Dave Brass - Len Lopresti - Eugene Rivera - Adrian Johnson - Travis Smith - Joseph Mineo - Jason Armstrong - Mike Healy - Gordon Wood - Eddie Hunt - Tom Robinson - Rick Heim - Vic D'Agnasti - Anthony Nowakowski - Lawrence Smith - Joseph Howard - Roger Brese - Carol Grace - Suzanne Fitzgerald