Under pressure from Congress to do something, de Blasio stepped onto the island for the first time in four years.
After a private tour, he expressed frustration at seemingly unfixable problems at the infamous jail.
"We have every step of the way tried to fix the problems here, but we had a massive, massive challenge with COVID which obviously set back so much of what we had done," de Blasio said.
The de Blasio administration has cut the inmate population in half since he took office eight years ago -- from 11,000 to around 5,600.
But over the past several months, a dozen inmates have died in custody and there have been more than 1,200 attacks on correction officers.
The city is blaming a dangerous understaffing problem, not because there aren't enough correction officers on the payroll, but because nearly a third of the ones who do work for the city are routinely calling in sick.
The city has sued the officers' union over alleged absenteeism.
"Not to speak to us, not to come here in four years and then blame us for the staffing crisis that he created? We're tired of being scapegoated," said Benny Boscio with the Correction Officers' Benevolent Association.
The union president is telling a different story - a story of a dangerous job in antiquated facilities and of a workforce ravaged by COVID and forgotten by a mayor intent on closing Rikers altogether.
Years ago, the mayor lent his support to an $8 billion plan to build four brand new detention facilities in four different boroughs and eventually close Rikers.
But that won't happen until 2026 at the earliest.
Boscio said the mayor let the jail fall apart because of his "ideology of closing Rikers." He said Monday's tour was sugar-coated.
"You walk in there now you can smell fresh paint," he said. "They moved the inmates out of the intake area and put them in another intake area. They didn't show him what he needed to see."
The mayor met with no incarcerated people Monday, he met with no correction officers, and he declined to say what it was about his visit that bothered him so much. He has only about 100 days left in office now meaning dealing with Rikers will be the next mayor's problem.
RELATED | Lawmakers tour Rikers Island, call conditions inside 'inhumane'
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