TRENTON, N.J. — Gov. Mikie Sherrill allowed Lt. Gov. Dale Caldwell to assume the full powers of New Jersey’s governorship on 18 days when she was out of state, even after her administration began an internal investigation into Caldwell’s conduct, according to public records and an examination of the governor’s public schedule. The investigation, which reportedly centers on Caldwell’s behavior toward women, began months before it became public. Caldwell has denied the allegations. Sherrill has not publicly confirmed that Caldwell is the subject of an investigation and has largely declined to discuss the matter. The governor’s office hired the law firm Lowenstein Sandler on May 21 at a rate of $450 per hour. The firm had billed nearly $50,000 to taxpayers by the end of June, according to a redacted retention agreement released in response to a public-records request. The agreement does not name Caldwell or explicitly describe the investigation, but it was provided in response to a request for records related to an inquiry involving the lieutenant governor. Caldwell stopped serving as acting governor after news of the investigation emerged publicly on Sept. 4, the start of Labor Day weekend. Since then, Sherrill’s public schedule shows no out-of-state travel beyond several short trips to New York City. The 18 days identified before that point included Aug. 18 and 19, when Sherrill traveled to New Hampshire and Massachusetts to campaign for candidates in Democratic primary contests. Her schedule does not make clear what she was doing during every day she was outside New Jersey. Under the New Jersey Constitution, the lieutenant governor becomes acting governor when the governor leaves the state. The role carries the governor’s full authority, including the ability to sign legislation, issue pardons and make appointments. In practice, the constitutional provision has not traditionally been applied to every brief trip across the border into a neighboring state. The episode has intensified questions from lawmakers in both parties about how Sherrill’s administration has handled the inquiry. Democrats, who control the Legislature, have pressed the governor’s office for more information. Republicans have focused on Sherrill’s decision to transfer executive authority to Caldwell while his conduct was under review. “If Mikie Sherrill thinks it’s responsible to leave the state on so many occasions including to campaign, while handing the reins to her lieutenant governor who is under investigation for alleged misconduct involving women, then she has truly abandoned her promise of transparency and accountability,” Republican state Chair Christine Hanlon said in a statement. Sean Higgins, a spokesperson for Sherrill, did not respond directly to questions about the investigation. Instead, he criticized Republicans over their positions on the president and the war in Iran, calling GOP complaints about accountability hypocritical. The lack of public information is particularly notable because Sherrill, a first-term Democrat and former Navy pilot, has built her public image around transparency and accountability. The governor’s office has not said when the outside counsel’s report will be completed or whether it will be made public. The investigation has also curtailed Sherrill’s travel and complicated the administration’s efforts to explain how executive power was exercised during the period under review. For New Jersey residents, the questions extend beyond the allegations themselves to the use of public money for the inquiry, the disclosure of the governor’s movements and the safeguards in place when a senior official under investigation holds the state’s top office temporarily.