A push by New York City jail officials to block people detained at Rikers Island from receiving physical mail was based on faulty fentanyl test strips that overstated the influx of contraband sent through the mail.

In 2022, New York City’s jails commissioner, Louis Molina, issued a dire warning to local lawmakers: fentanyl was pouring into Rikers Island through the mail, he said, spurring an overdose crisis among the jail’s detainees and putting guards at risk.

As evidence of the insidious threat, Molina passed around a child’s drawing of a reindeer, one of hundreds of seized items he said had been “literally soaked in the drug and mailed to people in custody.”

But that claim was based on faulty drug-testing kits with a stunning 85% false positive rate, according to a report released Wednesday by the city’s Department of Investigation. The report found the city vastly overstated the prevalence of fentanyl sent by mail to detainees.

When investigators retested 71 pieces of mail initially flagged by field tests as containing fentanyl, only 10 actually showed traces of the drug. The drawing of a reindeer highlighted by Molina was fentanyl-free.