The D.A.'s office said Lupo lied while testifying in Municipal Court about the Sept. 25, 2010, arrests of Joseph Tuamba and Angel Huffman.
Lupo testified that he went to inspect a Lincoln MKS that the two men were sitting inside of on East Chelten Avenue near Kenyon Street, because the windows on the car were tinted.
When he got close to the vehicle, he claimed he smelled marijuana. Tuamba and Huffman were both charged with possessing narcotics.
But three witnesses - including an agency operator from the Avis Rent-a-Car that owned the Lincoln - testified that the windows weren't tinted at all, the D.A.'s office said.
The charges against the men were withdrawn, court records show.
Investigators found Lupo also lied while testifying about the Aug. 5, 2011, arrest of Amiraria Farsi.
In that case, Lupo claimed that he and another officer noted a "huge odor of marijuana" when they stopped the Buick Regal that Farsi was driving near Baynton and High streets.
Farsi allegedly had narcotics and cash in his pockets, and was charged with three drug-related offenses.
Lupo stated that he waited for a search warrant and for a K9 Unit to arrive at the scene before he inspected the Buick's trunk.
But footage recorded by a nearby surveillance camera showed that Lupo had searched the car and the trunk before the warrant was approved and before the K9 arrived, the D.A.'s office said.
The charges against Farsi were withdrawn, according to court records.
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