By Gary Dymski

NYPD Commissioner William Bratton appealed to Silicon Valley Monday, urging the manufacturers of encryption software to help law enforcement agencies monitor terrorist activity by allowing them intercept capabilities.

Speaking on MSNBC's "Morning Joe" the dark technology that law enforcement suspects was used to plan the attacks on Paris, Bratton said tracking terrorists with technology is becoming more and more difficult because of end-to-end encryption.

Bratton said groups like the Islamic State are adept at going dark -- or communicating plans via encrypted messages that cannot be monitored. "They need to work with us right now," Bratton said of the manufacturers of such software. "In many respects, they are working against us."

Bratton's complaint echoes those made by other law enforcement leaders, including the FBI and the Joint Terrorism Task Force.

In July, FBI director James Comey told the Senate Judiciary and Intelligence committees that ISIS' use of end-to-end encryption helped the group place a "devil" on the shoulders of potential recruits "saying kill, kill, kill, kill."

Comey has called for debate about inserting "back doors" or "front doors" into encryption software, warning that "encryption threatens to lead us all to a very, very dark place."

Some technical experts contend that undermining encryption would do the opposite, opening doors for hackers, cybercriminals, foreign spies and terrorists.

Bratton said during the weekend that he believes such messaging systems will prove to have been "a significant factor" in planning the Paris attacks that claimed at least 129 lives.

"Basically, the technology has been purposely designed by our manufacturers so that even they claim they can't get into their own devices after they've built them," Bratton said during the MSNBC appearance.

Bratton mentioned the FBI's objection to the end-to-end encryption, too, and called the terrorists' ability to "go dark" a huge obstacle to law enforcement.

"Everyday we lose the ability to gather intelligence," Bratton said. "You have to be on the offense. Offense is intelligence.

"We are losing a lot of that intelligence momentum because of that issue."

Bratton also said the suicide vests worn by the Paris terrorists were something to study.

Currently, law-enforcement agencies are trained to be aggressive in such situations, to "rush in" and confront such terrorists, he said.

But Bratton said officials will need to determine the "ballistic capabilities of those vests."

Bratton said a team will be sent to Paris sometime this week to study the vests.

(c)2015 Newsday