Four years ago, Bill de Blasio campaigned as a police reformer, promising to end the "stop-and-frisk era." But as mayor, his record on policing has been both a political blessing and a curse. NY1 Political Reporter Grace Rauh filed the following report.

"We need one approach that will make the city safer — ever safer — by bringing police and community back together again," de Blasio said Oct. 20, 2013.

That was Bill de Blasio as a candidate with his eye on the prize. He promised a new rosy relationship between police and New Yorkers.

Instead, New Yorkers watched police put Eric Garner in a chokehold in 2014, killing him. Garner was unarmed, selling loose cigarettes. Massive protests erupted when no one was indicted for his death.

A few months later, two police officers were assassinated, and fellow officers turned their backs on de Blasio in a stunning rebuke.

"There's blood on many hands tonight," Patrolmen's Benevolent Association President Pat Lynch said on the night of the shooting. "That blood on the hands starts on the steps of City Hall in the office of the mayor."

The deadly events were a test for the mayor, and he responded by largely siding with police. He reversed the city's policy of sharing police disciplinary records, and he has not demanded punishment for Daniel Pantaleo, the officer who put Garner in a chokehold. De Blasio says his hands are tied while the Justice Department has the case open.

Regarding Rikers Island, however, he seemed to listen to activists.

"He can't hold himself out as this national progressive leader if he has this torture island in his own backyard," activist Glenn Martin said.

Under pressure, de Blasio made his move. "New York City will close the Rikers Island jail facility," the mayor said April 2, 2017.

He said it will take 10 years to close, which will be long after he has left office. For some, that's too long.

The city police department has undergone changes under de Blasio. Police are given sensitivity training, and some officers now wear body cameras, with the program set to expand.

But as de Blasio runs for re-election, the policing development that may matter most is his record on crime.

"Crime continues to fall," the mayor touted Tuesday.

Four years ago, political rivals warned that de Blasio would bring New York back to the bad old days when crime was rampant. Instead, it has remained at record-low levels overall on his watch.