Douglas Cox is an associate professor at the City University of New York School of Law. The views expressed are his own.

(CNN) While an FBI investigation into Hillary Clinton's email server continues, the State Department's Office of Inspector General has raised the stakes with the release of a remarkable report finding that Clinton's actions violated State Department policies and were inconsistent with federal record-keeping laws.

The report also discloses new details relevant to Clinton's motives and her assertion that the use of a private server was simply a matter of convenience. While criminal charges still remain highly unlikely, the inspector general's report is significant and unquestionably damaging to Clinton's public defense.

Most crucially, the inspector general directly contradicts Clinton's repeated assertions that she complied both with federal law and State Department policies. "At a minimum," the report finds, "Secretary Clinton should have surrendered all emails dealing with Department business before leaving government service and, because she did not do so, she did not comply with Department's policies that were implemented in accordance with the Federal Records Act."

The report goes further, noting that while Clinton's subsequent production of 55,000 pages of emails in response to State Department demands partially corrected these violations, the records Clinton turned over were incomplete. Remarkably, the report includes reference to a previously unreleased 2010 email in which Clinton, responding to her deputy chief of staff for operations, Huma Abedin, directly addresses her lack of an official State Department email account and voices a fear of the "risk of the personal being accessible" if she had one. In a briefing, State Department officials were unable to confirm the source of this email, but if it was omitted from the records Clinton produced, it again would raise questions about the process she used to distinguish between "federal records" and "personal records" before destroying the latter.

The inspector general also reveals the comments of State Department records management staff in late 2010 expressly raising concerns that Clinton's private email server "could contain federal records that needed to be preserved in order to satisfy federal record-keeping requirements." A senior official rebuffed these concerns, claiming that Clinton's email arrangement "had been approved by the department legal staff" -- an assertion the inspector general concluded was untrue -- and directed staff "never to speak of the secretary's personal email system again."

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Such facts undermine the argument that the significance of maintaining a private server and the negative effects it could have, including on responses to Freedom of Information Act requests or congressional subpoenas, were simply overlooked.

Clinton's response

Clinton's response to the report is further complicated by the fact that the State Department did not contest the inspector general's findings, concurred with its recommendations, and even acknowledges in its response that "the department could have done better at preserving emails." All of this would serve to undermine assertions by Clinton that the inspector general's conclusions are biased or politically motivated.

Indeed, thus far Clinton's response has focused on the argument that other secretaries of state also used private email. "Well there may be reports that come out," Clinton commented, "but nothing has changed. It's the same story. Just like previous secretaries of state I used a personal email, many people did. It was not at all unprecedented." And, it is true that the inspector general does not spare former Secretary Colin Powell from similar allegations, documenting his use of private email and his admitted failure to preserve those emails.

Yet this arguably only furthers the perception that the inspector general's review was both balanced and non-biased. And Clinton's response highlights how her defense -- which began with confident assertions that she followed all the rules and broke no laws -- has now been reduced to the argument that "others did it too" or that the rules she violated were not significant.

Criminal charges?

Despite the inspector general's report, criminal charges against Clinton remain highly unlikely. While the report provides previously nonpublic information relevant to Clinton's motivations, the available public evidence remains insufficient to illustrate two facts needed for a criminal charge -- that she knew that emails on her private server were classified and that she intentionally mishandled classified information.

Yet the inspector general's report also highlights the uncertainty that surrounds the precise scope of the current FBI investigation. To the extent the FBI has limited its inquiry to security issues and the possible mishandling of classified information, for example, the inspector general's report finding violations of the federal records laws potentially implicates a different criminal statute.

Removing, concealing, or destroying federal records, regardless of whether they are classified, can constitute a federal felony. But again, courts have generally required prosecutors pursuing this charge to prove that defendants knew they were violating the law, for which the evidence against Clinton appears to be lacking.

In the end, extracting the truth in the Clinton email controversy in the current polarized political environment remains a nearly impossible task.

Some have already begun to seize upon the inspector general's report, mischaracterizing it as clear evidence of a crime. And when the Department of Justice announces that it is not filing criminal charges -- as is both expected and perhaps inevitable -- Clinton will likely argue that it constitutes proof that she did nothing wrong.

Based on the publicly available evidence, the reality appears to be nuanced in a way that is satisfying to neither side.

Clinton violated the law, but committed no crime.