A police car sits across the street from the 1st...

A police car sits across the street from the 1st Precinct of Nassau County Police Department in Baldwin in this 2013 file photo. Credit: Steve Pfost

Nassau County’s top police officer panned the idea of installing bulletproof glass in squad cars, telling a state Senate panel Wednesday it would do more harm than good.

The costs are significant, the windows can’t be rolled up or down and cops can’t “hear what’s going on outside,” Nassau Acting Police Commissioner Thomas Krumpter told state senators who have floated the bulletproof glass idea after a fatal attack on two officers in Brooklyn in December.

“There are a significant number of logistical issues,” Krumpter said. “It can provide a level of security  . . .  but you’re not going to be able to roll down the window and you’re not going to be able to hear what’s going on outside.”

Krumpter added that “armoring a car” could be cost prohibitive and create a public perception problem by “walling off” officers from the public.

The Republican-led state Senate has been holding police safety hearings after two NYPD officers were gunned down in Brooklyn – an incident that followed public protests about police conduct. The decision by a Staten Island grand jury not to charge a police officer in the apparent choking death of Eric Garner sparked the demonstrations about police conduct. Gov. Andrew M. Cuomo, a Democrat, has said he'll push for a criminal-justice agenda in the wake of Garner's death.