He’ll have to ask his bosses at the NYPD.

Mayor de Blasio admitted that the NYPD’s extremely loose definition of reckless driving “doesn’t make sense” — but he deferred on considering whether department rules should be tightened … until he can be schooled on the matter by police officials, the mayor said last week.

At issue was a recent Streetsblog report that the NYPD had completely undermined the mayor’s promise to crack down on recklessly driving police officers and employees by deciding that they would only lose their parking placard if they acquired 15 camera-issued speeding tickets or five camera-issued red light tickets in any 12-month period.

The mayor seemed to be caught off guard that the NYPD put the “five or 15” threshold into the patrol guide last month — months after de Blasio had promised a serious crackdown on dangerous cops. But he seemed to acknowledge the limits of his abilities to control the NYPD.

“Is 15 speeding tickets in 12 months the threshold you wanted when you revealed your new policy last year?” Streetsblog asked Hizzoner at Friday’s press conference.

“Not if [it’s] civilian use of their car,” the mayor said. “I need to get clear if PD was putting that number in because they know a certain percentage of the time it’s in the line of duty or people are rushing to a job. But if that’s about civilian use, no that doesn’t make sense. So, let me get more on that.” (City Hall did not provide more info.)

The mayor was apparently referring to an NYPD policy that allows officers to use their personal vehicles for police work under certain circumstances.

“In general, a commanding officer may approve the use of a private vehicle on a case-by-case basis when it’s ‘essential for an investigation/operation’ and a department vehicle or public transportation is not appropriate or available,” NYPD spokesman Al Baker said in a statement issued later in the day Friday.

That, of course, left myriad unanswered questions, which we have posed to the NYPD (we will update this story if we hear back). But in any event, if cops may use their personal vehicles to speed (or violently arrest protesters) when it’s “essential” or if there’s just a shortage of squad cars, it seems likely that no cops will end up being disciplined for racking up 15 camera-issued speeding tickets, since those line-of-duty tickets would likely be fixed.

Reckless driving by police employees remains a serious problem in this city. As Streetsblog’s “S-cop-laws” investigation last year found, cops and NYPD employees are twice as likely to get camera-issued moving violation tickets than the general public. And camera-issued tickets are the true benchmark because officers are very unlikely to write up their fellow officers.

But until the mayor finds out more about cops’ use of their personal vehicles to drive recklessly in school zones, we’ll just have to life with it.