A judge has given Derek Chauvin’s lawyers permission to examine tissue samples from George Floyd’s body. It’s part of a former Minneapolis police officer efforts to cause his federal conviction violating Floyd’s civil rights after he was also sentenced for Floyd’s murder in 2020.

U.S. District Judge Paul Magnuson approved the order on Monday, agreeing to allow the defense to review Floyd’s heart tissue and fluid samples. This will be done to test the theory that Floyd died from a heart condition aggravated by a rare tumor, and not – as prosecutors claim – from suffocation caused by a white police officer pressing his knee on a black man’s neck for nine and a half minutes in May 2020.

Chauvin’s federal defense attorney for his appeal attempt, Robert Meyers, argued that Chauvin’s original attorney, Eric Nelson, failed to inform his client that an outside pathologist not directly involved in the case, Dr. William Schaetzel, contacted Nelson before Chauvin pleaded guilty and offered the unsolicited theory that Chauvin did not cause Floyd’s death.

Chauvin argues that this amounted to “ineffective assistance of counsel,” and it did seeks a new trial, saying he would not have pleaded guilty if he had known about the pathologist.

But federal prosecutors argued in court filings that Nelson made a reasonable “tactical decision” not to investigate an unverified opinion “offered by someone posing as an expert.”

The Supreme Court rejected the appeal against the murder verdict

They noted that Nelson consulted with other medical experts in preparation for Chauvin’s cases, including one who testified in state court, but that the jury in that case rejected Chauvin’s medical defense. Federal prosecutors have also noted that the legal barriers to success on an ineffective counsel claim are very high.

Nelson declined to comment Tuesday.

Chauvin was convicted in state court on charges of murder in 2021. i he pleaded guilty later that year in federal court for violating Floyd’s civil rights. He is currently serving his 20-year civil rights sentence and 22 1/2 years for murder in a federal prison in Texas.

US Supreme Court rejected Chauvin’s appeal his murder convictions last year.

Floyd’s death and his dying cries of “I can’t breathe” sparked protests around the world – some of which became violent — and forced a dealing with police brutality and racism.