A day after police officers at a funeral again turned their backs on New York Mayor Bill de Blasio, the mayor said those who used the service to stage a protest “showed disrespect” to the mourning families and the people of New York.

“They were disrespectful to the families involved,” de Blasio said Monday. “They were disrespectful to the families who had lost their loved ones. I can’t understand why anyone would do such a thing in the context like that.”

De Blasio’s comments marked his first expanded public reaction to the criticism he has received from union leaders and some officers, which extended to demonstrations at the funerals for the police officers who were shot and killed in Brooklyn last month.

He appeared Monday alongside Bill Bratton, the police commissioner, a news conference aimed at discussing the city’s crime rate, which dropped 4.6 percent in 2014 from a year earlier. The mayor heaped praise on the department for its efforts in 2014 while simultaneously dismissing “the loudest and most disrespectful voices” he said have dominated the news cycle.

De Blasio’s relationship with some members of the police force has deteriorated since Officer Wenjian Liu and Officer Rafael Ramos were gunned down while sitting in their squad car on Dec. 20. A large number of officers at the funeral for Liu turned their backs when de Blasio spoke on Sunday, mirroring the action officers also took more than a week earlier at the funeral for Office Rafael Ramos.

This occurred despite a request from Bratton that officers not repeat the “act of disrespect” that has drawn attention from the officers and onto the rift between the mayor and the police. Bratton said Monday he was disappointed with “the selfishness” of the officers who ignored his memo.

“Don’t put on your uniform and go to a funeral and engage in a political action,” he said.

Law enforcement officers say morale is falling among some rank-and-file police, owing to comments from President Obama and others about the need for police reforms. Some officers have said they feel under fire after months of protests regarding the deaths of Michael Brown in Missouri and Eric Garner in New York over the summer, demonstrations that only grew louder after grand juries opted not to indict the officers involved in either case.

In addition to the police protests and boos at a recent police academy graduation speech, De Blasio has been criticized by officials like former Mayor Rudolph Giuliani and former governor George Pataki. Patrick Lynch, the president of the Patrolmen’s Benevolent Association, the city’s largest police union, said there was “blood on many hands,” including de Blasio’s, hours after the shooting.

Lynch and de Blasio met for a meeting with other officials and union leaders last week. De Blasio declined to talk in great detail about the meeting when asked on Monday, but said only that he felt it was productive.

De Blasio said that the city’s police officers should be very proud of what they accomplished in 2014. This “extraordinary year” saw the crime rate drop amid decreased use of stop-and-frisk as well as the continued drop in the number of misdemeanor marijuana arrests, de Blasio said.

“It was possible all along to create a safer city and a fairer city,” he said.

New York saw 332 homicides last year, a drop from 335 a year earlier and a colossal decline from the record 2,245 murders in 1990, the police said. There were also fewer robberies, burglaries, rapes and felony assaults in 2014 than there were in 2013, according to police data released Monday.

However, the number of shootings did go up, while remaining below the 10-year average, police noted.

Fewer people were questioned using the controversial stop-and-frisk approach, making the third consecutive year that saw its use plummet. Police data released Monday also showed that the number of arrests made per stop increased since last year. Bratton said that stop-and-frisk was “here to stay,” but emphasized that it would be used appropriately.

While de Blasio and Bratton were largely focused on last year’s numbers, they also touched on more recent statistics. New York police officers have carried out fewer arrests and written fewer summonses over the last two weeks, which has raised the specter of an intentional work slowdown. However, both men said it was too soon to offer larger conclusions about what was happening.

[This post has been updated.]