(CNN) —  

A federal appeals court has rejected an effort by former Army intelligence analyst Chelsea Manning to be released from jail following a court holding her in contempt last month.

Manning was jailed last month for refusing to testify – likely against WikiLeaks or its founder, Julian Assange – to a federal grand jury in the Eastern District of Virginia.

She has been in jail since March 8.

Manning had argued her rights were violated by the grand jury subpoena proceedings and has accused the federal prosecutors of misusing the subpoena to entrap her.

The former Army intelligence analyst who was previously jailed for seven years for leaking classified documents to WikiLeaks was subpoenaed in March to testify. The grand jury activity was apparently the latest dust-up from the Justice Department connected to Assange and came weeks before Assange was arrested in London.

It was unclear why the grand jury still needs Manning a year after Assange was indicted under seal for conspiracy connected to Manning’s leaks. Prosecutors refused to tell a federal judge what they’d like to question Manning about. She is being held in jail until she acquiesces or the grand jury is no longer sitting, or until a higher court intervenes, which now looks less likely.