Allen, 20, who died three months after being shot, was a friend of the teenage boy who had assaulted Ellison's teenage son and had stolen a pizza from him that afternoon, sparking the clash.
Ellison and Fortune - who were off duty and dating - were right to drive around looking for the robber, the judge said.
"However, it was the manner in which these two conducted themselves which brings us here today," said Byrd, noting that the defendants did not call 9-1-1 or identify themselves as officers and that Ellison sped the wrong way down Renovo with a loaded gun pointed out the window.
"This is not your typical 'recklessly endangering another person' case, and it calls for a sentence above the guidelines," Byrd said.
He chided Fortune for the profanity-laced tirade that trial witnesses said she unleashed while goading Ellison to shoot Allen after the couple followed the pizza thief to the victim's block.
Witnesses said Allen - who left behind a wife and three children - had tried to calm the situation and had offered to pay for the pizza.
Ellison, 41, and Fortune, 45, were convicted in November of reckless endangerment, a misdemeanor, for which they each received the maximum sentence yesterday.
They were fired from the force in 2010 and charged in 2012.
The jury deadlocked on a charge of voluntary manslaughter against Ellison, a felony that carries a maximum sentence of 10 to 20 years in state prison. The jury also deadlocked on a misdemeanor count of conspiracy to commit reckless endangerment.
In addition to their jail terms, Byrd sentenced each defendant to one month of reporting probation after they are released, and ordered each to pay a $5,000 fine and to enroll in anger-management class while locked up.
They must surrender Feb. 21 to begin serving the jail terms, Byrd said.
Ellison testified at trial that he fired the fatal bullet after Allen drew a gun. Other witnesses testified that Allen was unarmed.
Before being sentenced, Ellison apologized to Allen's family, telling them that not a day passes that he does not think of the victim. He then turned to Byrd and said: "As God as my witness, that night Lawrence Allen had a gun, he pulled it on me and I had to defend myself."
Allen's widow, Rosemily Rosado, 25, called the apology self-serving and said both defendants should be retried. "Anyone who commits a crime that bad and that harsh," she said, "should be tried for it."
A decision on whether to retry the defendants on the deadlocked counts will be announced at a hearing Jan. 29, Assistant District Attorney Gail Fairman said.
"The jury, by its verdict, recognized that these individuals had misused their power, and in the arrogance of their power they created events that ultimately led to the death of Lawrence Allen," Fairman said.
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