For the five years he has held office, Gov. Christie has not declared any gifts on his annual financial disclosure forms.
The governor's office says Christie has complied with an executive order he issued in 2010 requiring disclosure of gifts of a certain value, but it won't say who paid for Christie's travel and ticket to a September 2013 Dallas Cowboys-New York Giants game in Texas, where he was seen in the owner's box with Jerry Jones.
His frequent appearances in luxury boxes with Jones this season have raised questions about what the governor has paid, whether he can accept such perks, and whether he needs or intends to disclose them under New Jersey's ethics laws.
Christie's office has acknowledged that Jones provided Christie's tickets to three games this season, as well as travel via private jet with his family to the Cowboys-Detroit Lions playoff game Sunday. His office would not say whether the governor has received any other gifts during his five-year tenure.
Christie would not need to report the tickets to this season's games until he files his next disclosure form, likely in May.
His predecessors, Jon S. Corzine and Richard J. Codey, also did not report any gifts during their terms. Former Gov. Jim McGreevey's forms were not available online.
The 2010 executive order, versions of which were signed by governors dating back to McGreevey in 2003, says "every public employee and public officer" in the executive branch, including the governor, must file disclosure forms detailing occupation, sources of income, and assets.
The order also compels disclosure of cash gifts greater than $100 and noncash gifts greater than $200. It does not specify a limit on the value of the gifts.
This contrasts with the state Ethics Commission's uniform code for executive branch employees, which requires the immediate disclosure of gifts to an ethics liaison officer. The commission says it holds a "zero tolerance policy for acceptance of gifts."
Exceptions include gifts from a coworker.
The Ethics Commission did not respond to questions about which set of rules - those outlined in the governor's executive order, or the commission's own code - took precedence.
Paula Franzese, a government ethics expert at Seton Hall University School of Law, said that Christie is subject to the governor's code and that he is required to disclose gifts on his annual financial disclosure forms.
A Cowboys spokesman said he assumed Jones provided Christie's ticket for the 2013 game, but wasn't certain. The spokesman, Rich Dalrymple, also could not say whether it was the Cowboys organization or Jones personally who paid for the ticket.
The tickets belong to the organization, and Jones can provide them to whomever he'd like, Dalrymple said.
"Mr. Jones has several guests in his suite," he said.
Christie's 2010 executive order says the governor may accept gifts paid for by "personal friends," though the rules don't define that term.
That exception is "broadly written," said Rob Kelner, chair of the Election and Political Law Practice Group at Covington & Burling in Washington.
"It leaves a lot open to question," he said. "Whether somebody you met while you were governor would qualify as a personal friend, I don't think the answer to that is clear."
In 2013, the Port Authority of New York and New Jersey approved a 15-year lease agreement with a company owned in part by the Cowboys to develop and operate the observation deck at One World Trade Center.
The Cowboys' Dalrymple declined to say how much tickets cost. A representative in the Eagles front office said that to reserve a box suite at Lincoln Financial Field for a game against the Cowboys, "you'd be looking at $20,000 for 20 tickets."
Christie, who says he is a longtime Cowboys fan, has attended five of their games this year, and they have won all of them. Images of the Republican governor, who is considering a run for president in 2016, celebrating with Jones have spurred an avalanche of commentary on social media and elsewhere about sports allegiances and politics.
Christie said this week that he hoped to attend Sunday's matchup between the Cowboys and Green Bay Packers at Lambeau Field in Wisconsin.
Kelner, the Covington attorney, said it was "probably not surprising" that New Jersey's gift rules for governors, defined in executive orders issued by governors, were less stringent than in states where such rules are imposed by statute. New York and Florida, among other states, have stricter rules, Kelner said.
The governor's code of conduct was established by McGreevey, a Democrat who resigned in 2004 amid an ethics scandal and an extramarital affair.
An advisory panel convened by McGreevey recommended that the governor be subject to a separate code of conduct than other employees of the governor's office.
The governor "faces an unending and often contentious array of public policy, economic, social, regulatory, and political demands," said an October 2003 report by the panel, whose members included former Attorneys General John Degnan and John Farmer, and retired state Supreme Court Justice Stewart Pollock.
A code of conduct "should reflect the wide-ranging nature of the position. . . . The code must allow the governor the flexibility to accomplish the job for which he was elected," the report said.
Flexibility wouldn't mean lower ethical standards, given that the governor is "the most extensively and intensively scrutinized official in the state," the panel said in the report. "Any perceived ethical lapse of the governor will be magnified by public scrutiny."