The Yankees, according to Brian Cashman, did their “due diligence” in vetting Aroldis Chapman before completing Monday’s trade for the troubled closer. But with Chapman still under scrutiny by both Major League Baseball and the Florida authorities, his transition to the Bronx could be a bumpy one — including the blowback from local lawmakers.

Bryan Seeley, a former assistant U.S. attorney and now MLB’s top investigator, is the point man for preparing reports on Chapman, as well as two other players currently being investigated for domestic violence: Jose Reyes and Yasiel Puig. Once that step is done, those reports will be turned over to commissioner Rob Manfred, who will then decide on the course of disciplinary action.

Under MLB’s new domestic violence protocol, there is no minimum or maximum penalty guidelines for Manfred to follow. And with no precedent, Manfred will be breaking new ground, which carries the pressure of determining a punishment that correctly fits the crime — whether charges ultimately are filed against Chapman or not.

After the public outcry over NFL commissioner Roger Goodell’s handling of Ray Rice and Greg Hardy, Manfred has motivation to come down hard on Chapman and the others. Though he could face some resistance from the Players Association — any discipline is subject to appeal — pushing for leniency amid domestic violence allegations is not a side anyone wants to be on.

MLB intends to rule on the Chapman case well before Opening Day and the expectation is that he will be suspended. Even if no new details arise, the fact that Chapman fired eight gunshots in his garage during the Oct. 30 incident at his Miami-area home is alarming enough to merit a penalty.

Considering that a first offense for a positive PED test carries an 80-game suspension, Manfred’s ruling will be evaluated in relation to that existing disciplinary structure, just as Goodell’s was compared to the NFL’s drug policy. Also, Chapman is 138 service days short of free agency — a full season is 172 days — so any suspension longer than approximately 30 games would make him wait until the end of the 2017 season instead of this one.

The Yankees already have been under fire for the trade, with New York City Council Speaker Melissa Mark-Viverito telling reporters Tuesday it was “really wrong” for them to trade for Chapman.

“He does admit to having fired those shots, OK, and it was related to a domestic dispute, so that’s extremely disturbing right there,” Mark-Viverito said. “It’s too much that raises alarm for me and I don’t think it’s a good message to send at all.”

A Yankees spokesman declined comment Tuesday, but Cashman said after Monday’s trade: “Certainly there are some serious issues here that are at play. I acknowledge that’s an area clearly of concern.”