The legal battles before Donald Trump are expansive and varied.

The former president is under investigation for everything from his handling of top secret documents to the price tag placed on his New York penthouse, and facing numerous lawsuits as well.

But four high-profile investigations could have the biggest impact on Mr Trump - personally and politically.

All are ongoing and have not resulted in criminal charges.

What's being investigated?

The Department of Justice is looking into the removal of government documents from the White House, which were then taken to Mr Trump's Florida estate, Mar-a-Lago, after he left office. Investigators are assessing how these documents were stored and who may have had access to them.

The former president's sprawling beachside property was searched in August and 11,000 documents were seized including around 100 marked as classified. Some of these were labelled top secret.

Unsurprisingly, we know very little about what's in the documents at this stage. But classified material usually contains information that officials feel could damage national security if made public.

What has Trump said?

He's denied wrongdoing and criticised the justice department's investigation, branding it "politically motivated" and a "witch-hunt".

He has offered shifting defences which have mostly hinged on the argument that he declassified the material. No evidence has yet been provided that this is true.

The former president has also argued that some of the documents are protected by "privilege" - a legal concept that would prevent them from being used in future proceedings. An independent lawyer is reviewing the seized material to determine if this is the case and that process continues.

But Mr Trump has not directly addressed the key question of why the documents were at Mar-a-Lago in the first place.

So how serious is it?

This is an active criminal investigation and could result in charges being filed.

Among other statutes, the justice department believes Mr Trump may have violated the Espionage Act by keeping national security information that "could be used to the injury of the United States".

And as well as charges relating to the classified documents themselves, prosecutors are also looking at obstruction of justice as another potential crime.

Mr Trump's team are now locked in a legal battle with the justice department over the investigation.

What's being investigated?

Prosecutors in New York are examining the Trump Organization, the former president's family company. There are two investigations in New York - one civil and the other criminal.

Letitia James, the New York attorney general, is leading the civil investigation (which cannot result in criminal charges) and has spent almost three years looking at whether the company committed various acts of fraud over several decades in the state.

These include allegedly overstating the value of real estate, such as golf courses and hotels, in order to get more favourable loans and better tax rates.

The years-long criminal investigation, meanwhile, is being led by the Manhattan District Attorney Alvin Bragg, and is looking into the same issue as they relate to operations in New York City.

What has Trump said?

The former president and his lawyers have insisted the company did not operate illegally.

He's accused Ms James, a Democrat, of pursuing a political vendetta, citing remarks she made before she was elected attorney general in which she vowed to sue him and branded him an "illegitimate president".

Mr Trump, when called for an interview in the civil investigation, refused to answer questions and only confirmed his name.

So how serious is it?

Ms James filed a fraud lawsuit in September that it could - in theory - lead to the Trump Organization ceasing to exist in its current form.

Ms James said the former president, his three eldest children and two company executives committed numerous acts of fraud between 2011 and 2021.

The lawsuit alleges that the family inflated their net worth by billions, and is seeking $250m (£226m) that was allegedly obtained through fraudulent means. It's also seeking various penalties, such as bans on Mr Trump and his children from serving in a leadership role in any New York business.

The criminal investigation has been quieter so far. Ms James, however, has referred her findings to federal prosecutors which could lead to a new criminal investigation being opened.

What's being investigated?

Mr Trump's alleged role in the attack on the US Capitol on 6 January 2021, when a mob of his supporters stormed the building in an effort to stop the confirmation of President Joe Biden's election victory, is under scrutiny from several federal government bodies.

The most visible has been a Congressional committee that has been looking into Mr Trump's actions. They've been holding televised hearings laying out their case that his election fraud claims led directly to the riot.

What has Trump said?

He's denied responsibility for the riot and criticised the Congressional committee, which he described as a "kangaroo court" and "unselect pseudo-committee".

He has continued to repeat his unsubstantiated allegations of widespread voter fraud.

So how serious is it?

The Congressional committee - made up of seven Democrats and two Republicans - does not have the power to prosecute, but it has voted to subpoena Mr Trump.

This means he is legally compelled to testify to Congress, but he's expected to defy the subpoena which will likely lead to a protracted legal battle.

The committee is also weighing up whether to make a criminal referral recommending that the justice department charge Mr Trump. This doesn't mean much in practice - but it could increase the pressure on investigators.

The justice department's criminal probe has already led to hundreds of people who stormed the Capitol being charged.

The former president has not been called for questioning in that inquiry, but it remains a possibility. He could also - in theory - be charged if investigators believe there is sufficient evidence of wrongdoing.

What's being investigated?

Prosecutors in the state are looking into alleged attempts to overturn the 2020 presidential election result.

The criminal investigation was opened after the disclosure of an hour-long phone call between the former president and the state's top election official on 2 January 2021.

"I just want to find 11,780 votes," Mr Trump said during the call to Republican Secretary of State Brad Raffensperger - a reference to the number of ballots needed to give him victory in the swing state.

What has Trump said?

He's described the investigation - as he has many others - as a "witch hunt".

Mr Trump has also attacked the legal official leading the inquiry - the chief prosecutor of Fulton County, Fani Willis - as a "young, ambitious, Radical Left Democrat... who is presiding over one of the most Crime Ridden and Corrupt places".

So how serious is it?

"The allegations are very serious. If indicted and convicted, people are facing prison sentences," Ms Willis told the Washington Post last month.

She added that a decision on indictments was not imminent, but said Mr Trump could soon be called to give testimony.

It is not known whether the former president is being directly investigated, but some of his allies are known to be part of the inquiry. One target is his former personal lawyer Rudy Giuliani, who led legal challenges to dispute the election result. Lawyers for Mr Giuliani have said he did not commit wrongdoing in the state.

It's reported that investigators are examining potential criminal wrongdoing in calls made to Georgia officials, as well as alleged false statements made to politicians there.

For a criminal conviction, however, prosecutors would ultimately need to prove beyond reasonable doubt that those involved knew their actions were fraudulent.