Mayor Bill de Blasio's plan to outfit all patrol police officers with body cameras by the end of 2019 is becoming a political headache. A source tells NY1 the city's contract for the cameras is being probed by the city's Department of Investigation. The Mayor spoke about the camera program in his weekly "Mondays with the Mayor" interview on NY1. Our Grace Rauh has the story.

It's all part of the mayor's push to reform the police department. By the end of 2019 all patrol officers will be outfitted with a body camera. But the roll-out is already hitting a road block. City Comptroller Scott Stringer refused to sign off on the city's contract for the cameras last Friday. Now, NY1 has learned that the city's Department of Investigation is probing the contract — a source from Stringer's office says that's what prompted the comptroller to hold off.

"Him raising policy concerns, he has a right to do it, but it doesn't stop the administration from moving forward with the contract," the mayor said.

NY1 spoke with Mayor de Blasio about the body camera contract before we learned about the investigation. The mayor suggested Stringer's objections were over the body camera program and not the actual contract.

"This contract makes sense," de Blasio said. "We don't see any problem with it. The company we feel good about, was the right choice. We will always respectfully look at anything the comptroller puts forward. I'm not going to pre-judge his motivations. If he's not working within the particular purview he is given by the charter, it does not stop us from moving forward with our work."

Sources close to the mayor confirmed that the Department of Investigation did begin looking at the contract months ago. They say investigators found no evidence that should have prompted Stringer to reject the contract. As de Blasio battles multiple investigations into his fundraising and political activities news of yet another investigation into his administration is bad news, especially in an election year. Stringer is considered a possible challenger to de Blasio in the mayor's race.

However, the mayor did get some good news on the public safety front this week.

January saw a record-low number of murders and shootings in the city. He was out promoting those figures on Monday — before news of the investigation broke.