The criminal background of several witnesses and a lack of corroborating evidence was loudly attacked by defense lawyers as closing arguments began in the trial of six Philly narcotics officer accused of robbing drug dealers and other members of the public.

Lead defense lawyer Jack McMahon called the federal prosecution against the officers "preposterous," "absurd," and "a tragedy against these men."

McMahon in particular took issue with the fact that many witnesses for the federal government claimed they had massive amounts of money stolen -- but there was no evidence the allegedly stolen funds ever existed.

“This is a case where the justice system and the investigation has run amok,” McMahon argued. “They [federal prosecutors] have made judgements before they were facts. They have failed at every level to verify and corroborate the most basic things.”

McMahon mentioned one witness, Kenneth Williams, who claimed the officers stole $14,000 in funds from a worker's comp settlement from his house. McMahon called Williams “a scammer” and said proof of Williams’ settlement was never introduced into court.

Another witness, Theodore Carobine, testified that officers planted 100 grams of meth in his house, then stole $10,000. McMahon questioned that, saying that much meth would have been worth $30,000.

McMahon pinned all illegal activity on Jeffrey Walker, a former member of the same squad as the indicted officers who was arrested in 2013 after trying to rob an undercover FBI agent and who is a cooperating witness in this case for the federal government.

However, prosecutor Maureen McCartney said "common sense, logic and reason" indicated that 19 different witnesses could not have come up with near-identical stories that matched Walker's testimony.

"There are no reasonable explanations for it except that these things happened and these defendants did them," she said.

McCartney also showed text messages that defendant Thomas Liciardello, the alleged ringleader of the group, sent Walker after finding out he had been interviewed by Internal Affairs investigators.

The texts include the message "Die rat," sent nine times in a row and “You are not loyal snitch” sent twice.

"He doesn't call him a liar," McCartney observed. "He calls him a snitch, he calls him a rat, but he never ever says, 'You're not telling the truth.' [Those] are the words of someone who has something to hide."

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