( CNN ) -- We do n't yet know what polluted swamp of mental sickness led Ismaaiyl Brinsley to embark on a multistate rampage that culminated with the barbaric , execution-style killing of NYPD Officers Wenjian Liu and Rafael Ramos on a New York City street . But the madman 's actions could not have happened at a worse time for a city already embroiled in a bitter public battle over police-community relations . It 's very possible that an important debate about race , policing and the proper use of force will be buried along with the martyred officers . Weeks of street protests over a grand jury 's decision not to indict police officers who killed Eric Garner -- along with Mayor Bill de Blasio 's statements in sympathy with the goals of the demonstrators -- had already antagonized police unions ( which , to make matters even more fraught , are in the middle of trying to settle a contract with the city ) . Even before the slaying of the officers , a war of words between de Blasio and union leaders had grown strikingly bitter , prompting New York 's most prominent cleric , Cardinal Timothy Dolan , to publicly call on both sides to ratchet down the rhetoric . The call for civility had n't yielded much in the way of results -- the unions continued to bash the mayor , and a street demonstration earlier this month for the first time turned violent , with a pair of police officers beaten on the Brooklyn Bridge . `` It 's not a time for political analysis , '' said a somber de Blasio at a press conference Saturday , shortly after meeting with the families of the slain officers . The mayor appeared shaken , in part because while entering the hospital where the dead officers ' bodies lay , he passed through a cordon of dozens of officers who pointedly turned their backs on him instead of saluting . De Blasio 's call for a temporary halt to political warfare did n't stop his adversaries from going on the attack . Typical of the criticism was a Twitter message from former Gov . George Pataki , a Republican who has been floating trial balloons about a possible run for president . Pataki pronounced himself `` sickened by these barbaric acts , which sadly are a predictable outcome of divisive anti-cop rhetoric of Eric Holder and Mayor de Blasio . '' The statement is farfetched to say the least : Neither Pataki nor anybody outside the psychiatric profession has the slightest idea why Brinsley shot his girlfriend , traveled hundreds of miles to New York , randomly killed two policemen and then took his own life . Boldly claiming that the mayor and attorney general led Brinsley to murder by mere words raises a question Pataki ca n't possibly answer : Which speeches , exactly , made it all happen ? An even harsher tone came from police union leaders . `` There is blood on many hands tonight , '' said the president of the Patrolmen 's Benevolent Association , Patrick Lynch . `` Those that incited violence on the street in the guise of protest , that tried to tear down what New York City police officers did every day . We tried to warn it must not go on , it should n't be tolerated . That blood on the hands starts on the steps of City Hall , in the office of the mayor . '' Watching the turmoil on television , you 'd never know that New York is on track to register the lowest number of murder and other serious crimes since the city began tracking numbers in the 1960s . The city has never been safer -- but rarely has it seemed so divided and angry . Both sides are guilty of excess and poor judgment . `` Lynch 's fulminations about legitimate policy differences have been destructively overheated , '' the New York Daily News said in a recent editorial , condemning the union president for circulating a form officers can complete that asks de Blasio not to attend their funerals if they end up killed in the line of duty . The mayor , who has openly supported the sentiment of demonstrators protesting the police killing of Garner , made mistakes of his own . De Blasio should have issued a harsh rebuke to activists who recently marched through the streets chanting `` Shoot Back ! '' and `` What do we want ? Dead cops ! '' The mayor should have agreed to Lynch 's demand that protest leaders loudly and publicly disavow such violent rhetoric . Can things get worse ? Yes , they can . In 1992 , cops upset at then-Mayor David Dinkins staged a rally at City Hall that turned into a near riot , with 10,000 officers taking over a bridge , tramping on cars , and booing and cursing at superior officers and elected officials . We have n't reached that point in New York -- yet . But these are dark , troubled times in an urban center where 20 years of dedicated effort by police and community have mostly conquered the true , common enemy -- the city 's criminals , who are surely enjoying the discord that allows them to thrive in our divided city .
Errol Louis : Killing of two NYPD officers could not have come at a worse time for the city . New York is already embroiled in a bitter public battle over police-community relations , he writes . The killing of two police officers, one black and one Hispanic, has put an end to what was supposed to be a peaceful protest against recent grand jury decisions that cleared white cops involved in killings of unarmed Louis calls that `` farfetched '' but says mayor should have disavowed violent rhetoric .