Image copyright The Washington Post via Getty Images Image caption Ralph Northam's page in the 1984 yearbook of Eastern Virginia Medical School - one of several blackface photos in the publication

An independent inquiry into a racist photo on Virginia Governor Ralph Northam's 1984 college yearbook page has ended with no conclusive findings.

The report could not determine the identities of two individuals, one in blackface, the other in Ku Klux Klan robes, in the image.

The inquiry followed back-to-back controversies involving the Democratic governor and state leaders in February.

Mr Northam initially apologised for the photo, but then said it was not his.

"With respect to the photograph on Governor Northam's personal page, we could not conclusively determine the identity of either individual depicted in the photograph," said the report.

The investigation was conducted by a law firm hired by Mr Northam's alma mater, Eastern Virginia Medical School.

"No individual that we interviewed has told us from personal knowledge that the Governor is in the Photograph, and no individual with knowledge has come forward to us to report that the Governor is in the photograph."

The investigators also noted that they were unable to determine whether the photo was placed on Mr Northam's page in error or by someone else.

It said the inquiry "was restricted by the passage of time and the dearth of the contemporaneous documentation".

Image copyright Reuters Image caption Ralph Northam and his wife, Pamela

Mr Northam issued a statement on Wednesday again denying that he was in the "racist and offensive photo" on his yearbook.

"That being said, I know the events of early February and my response to them have caused hurt for many Virginians and for that, I am sorry," he said.

"I felt it was important to take accountability for the photo's presence on my page, but rather than providing clarity, I instead deepened pain and confusion."

What's the background?

In February, Virginia's Democratic leadership was rocked by scandals that made headlines nationwide.

It began when a conservative website published the photo from Mr Northam's 1984 Eastern Virginia Medical School yearbook page.

The governor apologised hours later, seen by many as a tacit admission that he was one of the two individuals in the explosive picture.

But the next day he backtracked, saying: "I am not the person in that photo."

At the same time, he revealed he did once wear blackface when dressing up as pop star Michael Jackson for a contest in the 1980s.

Calls for Mr Northam's resignation were swift, coming from black legislators and top Democrats like former Vice-President Joe Biden and Senators Kamala Harris and Cory Booker.

But Mr Northam refused to leave his post, instead saying he would demonstrate "without a shadow of a doubt that the person I was then is not the person I am today".

Image copyright Getty Images Image caption Protesters gathered outside the governor's mansion in February

How did Northam weather the storm?

In the months since, the Democratic governor has focused on issues particularly relevant to his black constituents:

He vetoed two bills on mandatory minimum sentencing because he said the measures would disproportionately impact African-Americans

He started a review of the public school curriculum to ensure proper coverage of African-American history

He ended a policy of suspending driver's licences over unpaid court fees and created a new government position: the director of diversity, equity and inclusion

State Republicans have been quick to criticise Mr Northam's policy decisions as a means of atoning for his earlier scandal, instead of properly governing the state.

Republican leader Todd Gilbert called the governor's vetoes an "unconscionable" attempt "to repair his own racist legacy".

Rob Bell, the Republican chair of the House Courts of Justice Committee, said Mr Northam was pandering "to rehabilitate his political legacy".

According to an April survey by the Wason Center for Public Policy, though Mr Northam's approval rating dipped 19 points after the controversy, 52% of Virginians polled believed he should stay in office. Among black voters, notably, that number rose to 63%.

In addition to Mr Northam's controversy, Virginia's Attorney General Mark Herring apologised for wearing blackface in college.

And two women accused the state's Lieutenant Governor Justin Fairfax of sexual assault. He denied the claims. Mr Herring and Mr Fairfax also remain in office.