Classified documents: how do the Trump and Biden cases differ?

The discovery of documents from the Biden-Obama administration in at least two locations linked to Joe Biden has been greeted with dismay by Democrats and glee by Republicans, given the extensive legal troubles that Donald Trump faces for taking classified papers to his Florida resort.

Republicans believe the incident shows that Biden has committed the same transgression as the former president, and argue that the FBI raid on Mar-a-Lago and subsequent investigation were politically motivated point-scoring.

But Democrats insist the two incidents are different legally, while acknowledging that they present a political problem for Biden that allows Republicans to go on the offensive.

So what is the real situation? Here are the key points to know:

The FBI search at Mar-a-Lago last summer discovered more than 11,000 documents and photos from the Trump administration. They reportedly included highly classified intelligence material as well as more mundane papers. Subsequently more documents were also found.

Both situations are being investigated by the US Department of Justice, which will look into the behavior and possible motivations for taking the documents.

Trump appears to have willfully obstructed efforts to recover them, leading to the FBI raid, and the decision by the attorney general, Merrick Garland, to launch a criminal inquiry and appoint a special counsel to weigh charges on the issue as part of a broader brief looking at investigations into Trump.

With Biden, his team said they cooperated fully and immediately returned the documents to the National Archives as soon as they were discovered. Garland has asked John Lausch, a Trump appointee as US attorney for the northern district of Illinois, to conduct a review, but has initially resisted Republican calls for a criminal investigation or special counsel.

The Biden documents also reportedly contained classified papers commingled with non-classified materials, with the subjects and content yet unknown.

The Mar-a-Lago raid had mixed impact for Trump. Many Republicans despaired at having to defend the former president, while others backed his claims that he was being unfairly targeted.