US President Joe Biden’s son Hunter Biden was convicted by a jury on Tuesday of lying about his drug use to illegally buy a gun, a verdict Democrats may seize upon to counter Donald Trump’s claim of a justice system weaponised against him.

A 12-member jury in Wilmington, Delaware, federal court found the defendant guilty on all three counts against him, making Hunter the first child of a sitting US president to be convicted of a crime.

Hunter, 54, lightly nodded his head after the verdict was read but otherwise showed little reaction. He then patted his lawyer Abbe Lowell on the back and hugged another member of his legal team.

He then left the courthouse without making a statement.

His father issued a statement saying he accepted the outcome of the case and would respect the judicial process as his son considers an appeal.

The judge set no date for sentencing but added the timeline is usually 120 days.

That would place it no later than a month before the November 5 US presidential election.

Sentencing guidelines for gun charges are 15 to 21 months, but legal experts say defendants in similar cases often get shorter sentences and are less likely to be incarcerated if they abide by the terms of their pretrial release.

Some 61 per cent of registered voters responding to a Reuters/Ipsos poll in February said Hunter Biden’s legal troubles would have no impact on whether they voted for his father in November.

The poll showed voters divided over whether Hunter’s legal troubles were related to his father’s service as president.

The trial followed the May 30 criminal conviction of Trump, the first former US president to be found guilty of a felony and the Republican challenger to Joe, a Democrat, in a tight race for the White House.

Trump, convicted on 34 felony counts of falsifying business records to cover up a sex scandal, accuses Democrats of pursuing that case and three other criminal prosecutions to prevent him from regaining power in his rematch with Joe.

Congressional Democrats have pointed to cases, including the Hunter prosecution, as evidence that Joe is not using the justice system for political or personal ends, having said last week he would not pardon his son if convicted.

In a statement on Tuesday, Joe said: “As I said last week, I am the president, but I am also a dad. Jill and I love our son, and we are so proud of the man he is today.

“So many families who have had loved ones battle addiction understand the feeling of pride in seeing someone you love come out the other side and be so strong and resilient in recovery.

“As I also said last week, I will accept the outcome of this case and will continue to respect the judicial process as Hunter considers an appeal. Jill and I will always be there for Hunter and the rest of our family with our love and support. Nothing will ever change that,” the statement said.

The Hunter case was brought by US Department of Justice Special Counsel David Weiss, a Trump appointee.

Weiss has also charged Hunter with three felony and six misdemeanour tax offences in California, alleging he failed to pay $1.4 million in taxes between 2016 and 2019 while spending millions on drugs, escorts, exotic cars and other high-ticket items.

Hunter has pleaded not guilty to those charges. A trial is scheduled for September 5 in Los Angeles.

The Delaware trial included prosecution testimony by Hunter’s ex-wife, former girlfriend and sister-in-law, who gave firsthand accounts of his spiralling addiction in the weeks before and after he bought the gun in October 2018.

Prosecutors also showed text messages, photos and bank records that they said showed Hunter was deep in the throes of addiction when he bought the gun and knowingly broke the law by answering no to being a drug user on a government screening form.

His lawyers sought to show he was not using drugs when he bought the gun and did not intend to deceive because he didn’t consider himself a drug user when he filled out the form.

The defence called Hunter’s daughter, Naomi Biden, who testified that her father seemed to be doing well when she saw him shortly before and after he bought the gun.