Phoenix ? An investigation into whether politicians violated gift and disclosure laws when they accepted free game tickets or trips from the Fiesta Bowl led a prosecutor to conclude Wednesday that a maze of state laws was so complex and contradictory that he cannot pursue charges.

Inconsistent rules, vague reporting mandates and a legal requirement that prosecutors prove a defendant “knowingly” violated the law were major factors in his decision, Maricopa County Attorney Bill Montgomery said. In the end, there was not enough evidence to press charges against any of the 31 elected officials and three lobbyists who were investigated.

Montgomery said that for a successful prosecution, his office would have to prove that the officials and lobbyists knew when they filed required disclosure statements that “it was incomplete or false.”

“I understand the ‘appearance of impropriety’ argument, and how it can be reported,” Montgomery said. “But there’s a difference … in what it looks like and what we can do as prosecutors.”

Montgomery cited problems with records provided by the Fiesta Bowl, noting that many were too vague to stand up in court or directly contradicted reimbursement check records from legislators.

The decision removed a pall that has been cast over many lawmakers since April, when Montgomery began investigating whether politicians violated a law banning acceptance of free game tickets in most cases and failed to report receiving free trips or tickets.

Montgomery called on the Legislature to overhaul and consolidate reporting and gift laws for lobbyists and elected officials, toughen reporting requirements, ban gifts outright and make some violations a felony. He said changes were needed “in order for the public’s expectation of open and honest government to be met.”

Combining the laws into one simplified statute will help clear up confusion and help prosecutors if they need to pursue a case, he said.

He advocated the gift ban or, at the least, the allowance of only gifts of very low retail value. Under his recommendations, elected officials should accept “nothing — you can accept a handshake and that’s it,” Montgomery said.

He said he wants a law to require quarterly financial reporting, up from the current yearly mandate, and an online system for easier compliance.

In addition to a possible felony charge for “knowing and intentional” violations, Montgomery wants clarifications that allow misdemeanor criminal or civil penalties for reckless reporting failures. He suggested that legislative staff attorneys be removed from their role advising lawmakers, to avoid any attorney-client privilege issues.

Federal authorities are separately investigating other aspects of the Fiesta Bowl scandal, including an alleged scheme to reimburse employees for political contributions. One former executive has been charged in that case.

The county attorney’s probe was prompted by an internal bowl investigation into illegal political contributions and lavish spending by top bowl officials. Montgomery took over the case after the Arizona Attorney General’s office declared a conflict of interest.

That internal probe, released in March, listed many current or former lawmakers as the recipients of game tickets or free trips. Many failed to report them on their disclosure reports. The Fiesta Bowl asked politicians who received more than $161,000 worth of free trips or game tickets to explain how they benefited the tax-exempt group, and implied it may seek repayment if the expenditures can’t be justified. Some had already done so.

Montgomery investigated 28 current or former state lawmakers, three elected officials who are not legislators, and three prominent lobbyists. The politicians were split about evenly between Democrats and Republicans.

The 8-month probe involved going through 4,000 pages of documents that included nearly 10 years of financial disclosure statements, Montgomery said.

Senate President Steve Pierce, a Republican, referred inquiries to the spokesman for the chamber’s Republicans, who was not immediately available. House Minority Leader Chad Campbell said in a statement that Democrats support the ethics reforms and gift bans that Montgomery outlined.

The county attorney said some lawmakers told his office that they accepted the trips as ambassadors of the state, not for personal benefit or enjoyment. Some disclosed them routinely, while others failed to do so until the scandal hit and then filed amended reports. Former state Senate President Russell Pearce typically disclosed all gifts, tickets and trips, but not the Fiesta Bowl trips, which Montgomery said could indicate the Republican legislator believed he did not have to report those items.

“There were some legislators who were angry that I was investigating them because they thought it was clear they had done nothing wrong,” Montgomery said.

Topping the recipients were Pearce, who received more than $39,000 in tickets, trips and other freebies. From 2002 through 2009, Pearce went on VIP trips sponsored by the Fiesta Bowl to games in Denver, San Francisco, Chicago, Atlanta, Pasadena, Boston and Dallas. Other top recipients were former Republican lawmaker Robert Blendu with $17,213, and Democratic state Sen. Linda Lopez with $16,877.

Longtime bowl President and CEO John Junker was fired after the internal investigation. On June 13, the bowl hired University of Arizona President Robert Shelton to lead the efforts to repair its reputation. The bowl’s lawyer said it has been cooperating with local, state and federal investigations and made substantial changes to avoid a repeat.

The scandal at the Fiesta Bowl, which also hosts the national football championship every four years, put its role as one of the four top-tier bowl groups in jeopardy. But it avoided the worst sanctions — the loss of the championship game and its NCAA license.

The Bowl Championship Series fined the Fiesta Bowl $1 million, and the NCAA placed it on probation for a year.