Federal courts will probably "kill" President Donald Trump's latest attack on one of his political foes "in the cradle" before the case gets off the ground, a legal analyst said Thursday.

Adam Klasfeld, editor-in-chief of All Rise News, discussed a subpoena that Trump-aligned prosecutor, Acting U.S. Attorney John Sarcone, served to New York Attorney General Letitia James with progressive YouTuber Brian Tyler Cohen on Thursday. The subpoena concerned James' investigatory files from when she prosecuted Trump for fraud, Klasfeld said. James appeared in court on Thursday to fight the subpoena, where her lawyers argued that Sarcone is improperly serving as the acting U.S. attorney.

Klasfeld noted that Sarcone has not presented his case to a grand jury yet, and that the paperwork he sent to James amounts to a "signature at the bottom of an investigation."

"This is something that hasn't gotten off the ground, and the judge is going to find essentially whether to kill it in the cradle because there is no lawful prosecutor who is bringing these subpoenas, and she could find [Sarcone] cannot be involved in this case," Klasfeld said.

Sarcone is not the first one of Trump's interim U.S. attorneys to have their appointment challenged. Recently, a federal judge in the Eastern District of Virginia found that interim U.S. Attorney Lindsey Halligan was improperly appointed to her role, which ended the Trump administration's mortgage fraud investigation into James.

Klasfleld noted that these prosecutions could not have been challenged if a line prosecutor had participated.

"There would be no argument based on improper appointment if a line prosecutor... signed those subpoenas," Klasfeld said. "So, the fact that they didn't do that, the fact that Trump keeps installing acting and interim US attorneys who cannot get Senate confirmation or the approval of the judges of the district, is what keeps bringing us here."