A report from Special Counsel Robert Hur has raised serious questions about Joe Biden's memory, provoking a strong reaction from the US president.

Declining to prosecute Mr. Biden for retaining troves of classified documents, Mr. Hur - who served in the Trump administration - said the 81-year-old would likely present himself at trial as “a sympathetic, well-meaning, elderly man with a poor memory”.

Elsewhere, the report challenged Mr. Biden for retaining reams of classified information, and for storing it improperly and insecurely.

Shortly after the report was released, President Biden held a surprise news briefing at the White House, telling reporters: "My memory is fine.”

1. Major questions raised about the president's memory

The report found that the president's memory “appeared to have significant limitations”.

The quotes are among dozens of examples in the report which raise questions about Mr. Biden's memory and mental agility.

In one passage, the special counsel described an extended interview with the ghostwriter of Mr. Biden's book, Mark Zwonitzer, where the president appeared to struggle to recall significant events from his time serving as vice-president to Barack Obama.

“Mr Biden's recorded conversations with Zwonitzer from 2017 are often painfully slow, with Mr. Biden struggling to remember events and straining at times to read and relay his own notebook entries.”

The report then details Mr. Biden's interviews with the special counsel's office, for which he sat voluntarily, six years later. It describes his memory as having become worse in the intervening period.

“In his interview with our office, Mr. Biden's memory was worse. He did not remember when he was vice president, forgetting on the first day of the interview when his term ended ('if it was 2013 - when did I stop being Vice President?'), and forgetting on the second day of the interview when his term began ('in 2009, am I still Vice President?').”

Elsewhere, the report says Mr. Biden struggled to remember key events that caused divisions in the early days of the Obama administration.

In particular, it suggests that Mr. Biden struggled to describe the intricacies of a debate surrounding the surge of troops into Afghanistan in 2009. The then vice-president was opposed to President Obama's decision to send 30,000 additional US troops into the country to support the government of Hamid Karzai. Instead, Mr Biden wanted to expand special operations missions and drone strikes.

“His memory appeared hazy when describing the Afghanistan debate that was once so important to him. Among other things, he mistakenly said he “had a real difference” of opinion with General Karl Eikenberry, when, in fact, Eikenberry was an ally whom Mr. Biden cited approvingly in his Thanksgiving memo to President Obama.

Elsewhere, Mr. Hur's report also suggests Mr. Biden could not recall when exactly his son, Beau, passed away.

“He did not remember, even within several years, when his son Beau died.”

The president's son, a former US army soldier in Iraq and Delaware's ex-attorney general, died in May 2015, aged 46. Mr. Biden has described the event as one of the worst days of his life.

While Mr. Hur's report offers these examples as evidence of Mr. Biden's diminished mental faculties, the report has already come under attack from Democrats.

Richard Sauber – Mr. Biden's special counsel - condemned the report and urged Mr. Hur to “revisit [his] descriptions of President Biden's memory and revise them so that they are stated in a manner that is within the bounds of your expertise and remit”.

Mr. Sauber said the descriptions of the president's memory were not “accurate or appropriate” and that they had no place in a Department of Justice report.

Mr. Sauber also observed that the interviews began the day after the Hamas attack on Israel on 7 October last year, and that Mr. Hur seemed to accept it was reasonable that other witnesses could not recall events which, in some cases, occurred almost 15 years ago.

2. Biden stored classified documents next to a dog bed

In another section of the report, Mr. Hur described how investigators who raised Mr Biden's home in Delaware found scores of classified documents relating to Afghanistan in his cluttered garage.

The report said the files were discovered “near a collapsed dog crate, a dog bed, a Zappos box, an empty bucket, a broken lamp wrapped with duct tape, potting soil, and synthetic firewood".

But it noted that a “reasonable juror could conclude that this is not where a person intentionally stores what he supposedly considers to be important classified documents, critical to his legacy”.

Instead, Mr. Hur once again raised questions over Mr. Biden's memory, saying the discovery looked “like a place a person stores classified documents he has forgotten about or is unaware of”.

3. Biden thought Obama was making a major mistake with Afghanistan surge

Shortly after coming to office, Mr Obama became convinced that a surge of US forces into Afghanistan was the only way to maintain stability in the country.

Mr. Biden, as previously stated, was strongly opposed to the policy.

The then vice-president viewed himself as “a historic figure” who frequently maintained diaries and records with a view to later writing his legacy.

The report says Mr. Biden had a strong motive to keep the classified documents about Afghanistan because he wanted to prove that he was opposed to Mr. Obama's decision to send extra troops there.

He “believed President Obama's 2009 troop surge was a mistake on par with Vietnam”, the report states, adding: "He wanted record to show that he was right about Afghanistan; that his critics were wrong.”

4. Contrast drawn with evasive Trump

Mr. Hur credits Mr. Biden with immediately handing over the documents to investigators after he found them.

“Mr. Biden turned in classified documents to the National Archives and the Department of Justice, consented to the search of multiple locations including his homes, sat for a voluntary interview. and in other ways cooperated with the investigation."

And he drew a strong distinction with former President Donald Trump, who he says adopted the opposite approach. Mr. Trump is facing multiple charges for obstructing efforts to investigate the storage of the files at his Florida home. He denies the charges.

“Unlike the evidence involving Mr. Biden, the allegations set forth in the indictment of Mr. Trump, if proven, would present serious aggravating facts.

Most notably, after being given multiple chances to return classified documents and avoid prosecution, Mr. Trump allegedly did the opposite. According to the indictment, he not only refused to return the documents for many months, but he also obstructed justice by enlisting others to destroy evidence and then to lie about it.”

5. It was reasonable for Biden to keep some classified diaries

Mr. Biden has long kept notebooks in which he would write classified information during meetings.

The report noted that during his eight years as vice-president, Mr. Biden regularly kept notebooks that included details of classified subjects, including the President's Daily Brief and National Security Council meetings.

These notebooks were later removed from the White House and discovered in unlocked drawers and from the basement of his Delaware and Virginia homes. Mr. Biden, the report said, was aware the notebooks contained classified information but still read aloud from them to his ghostwriter.

But the report accepts that given the precedent set by former President Ronald Reagan - who also kept notebooks filled with classified information - that it may have been reasonable for Mr. Biden to believe that he had a right to hold onto the information. (BBC)

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