A US federal judge has stated that investigative missteps and government misconduct may have tainted the Trump administration's case against former FBI director James Comey.

Judge William Fitzpatrick ordered justice department lawyers to release grand jury materials, including transcripts and evidence, to Mr. Comey's defense team. The justice department has appealed against the order.

Mr. Comey, indicted in September for making false statements and obstruction of justice at the behest of Donald Trump, has pleaded not guilty to the charges.

After leading the investigation into Russian interference in the 2016 US presidential election, Comey became a frequent target of Trump. Charged with lying to lawmakers in 2020, Comey's legal woes escalated when new prosecutor Lindsey Halligan was appointed, leading to his indictment.

Judge Fitzpatrick criticized Halligan for her handling of the grand jury proceedings, citing statements that could mislead jurors regarding the evidence. He emphasized the need to protect the rights of the accused by allowing his defense access to all grand jury materials and audio recordings.

The judge's 24-page opinion detailed concerns about Halligan’s conduct, underscoring the gravity of the situation and the potential implications for Comey's defense.