Defense lawyer Jack McMahon turned to a Philadelphia jury Tuesday afternoon and told them to set aside their emotions.

The case before them, he acknowledged, was a horrific one: the triple killing of Porfirio Nunez, his wife Juana "Carmen" Nunez, and his sister Lina Sanchez, in their family bodega in West Philadelphia. All three were gunned down by the men who held up Lorena Grocery on Sept. 6, 2011.

And a week ago, the jury had listened to wrenching testimony from Jessica Nunez, the couple's daughter, who had seen the slayings and tearfully, adamantly identified the defendants, Ibrahim Muhammed and Nalik Scott, from the stand.

But the men's defense lawyers have contended from the beginning of this two-week trial before Philadelphia Common Pleas Court Judge Glenn Bronson that the identifications were mistaken, shaped by stress and fear.

And they hammered that point Tuesday in closing arguments, touching on everything from discrepancies in witnesses' descriptions of the suspects to gaps in police paperwork on the case to video footage that, they said, proved authorities had the wrong men.

"We have this innate desire to soften the pain for the Nunezes," McMahon said. "But giving into that innate desire would simply be another tragedy."

McMahon, who is representing Scott, and Larry Krasner, representing Muhammed, have contended that police didn't follow other leads on the case after Muhammed confessed - a confession they say is false.

In an unusual move, the defense has used evidence and eyewitness testimony from two bodega robberies that police say are connected to the Nunez killings, to argue that their clients never committed those robberies - and thus could not have killed the Nunezes.

Prosecutors say it was dogged investigation of those robberies that eventually led them to Muhammed. He was sent to homicide detectives after Detective Joe Murray of Southwest Detectives said he recognized him from a video taken from one of the robberies.

Defense lawyers have argued, in days of testimony, that Muhammed wasn't the man in that video, isolating screen shots of the man's facial features.

On Tuesday, Krasner said detectives investigating those robberies should have better followed up on fingerprint evidence, and criticized Murray for testifying at an earlier hearing that he had recognized Muhammed by "his Osama bin Laden nose."

And both defense lawyers highlighted two alibi witnesses who came forward last week and testified that Muhammed was with them at the time of one of the related robberies.

In his own closing argument, McMahon argued that Detective Thomas Gaul took a confession from Muhammed while he was off his medication for schizophrenia and highly suggestible. And Scott, he has said, became a suspect only after Muhammed confessed.

McMahon said police had not followed up on a man whom Jessica Nunez spotted in a bodega where she was working some months after the slayings; the man, she said on the stand, looked so much like one of the killers that she fainted. But police paperwork at the time stated she had identified the man as the killer himself - though Gaul has said that was a mistake.

"Words have meaning," McMahon said Tuesday. "It's revisionist history."

He said police gave up on the lead after Muhammed confessed.

Earlier in the case, a prosecution witness who saw the killers cross the street just before the slayings testified that he had come forward only because he didn't want to be suspected in the case himself.

"Mistaken identity happens all the time," he had said under cross-examination. "This is Philly."

The line was a touchstone for McMahon and Krasner on Tuesday afternoon. "Don't let it happen here," McMahon told the jury.

Prosecutors are to begin their closing arguments Wednesday.

215-854-2961 @aubreyjwhelan