A Manhattan judge Wednesday found the Princeton grad accused of killing his hedge-fund-founder dad when he cut his allowance, fit to proceed to trial — again.

Justice Melissa Jackson ordered a psychiatric evaluation of Thomas Gilbert Jr. last June after prosecutors revealed that he had swallowed a battery while locked up at Rikers Island.

Gilbert, 31, had also bizarrely requested that the Iraqi consulate be subpoenaed as a witness in the case, according to his lawyer Alex Spiro who requested the exam.

Despite the odd behavior, the court shrinks found that Gilbert was not mentally ill enough to be sent to a psychiatric facility for treatment.

Spiro said Wednesday in Manhattan Supreme Court that he did not agree with the findings, and that “the inner-workings of his (Gilbert’s) mind are not really susceptible” to this type of evaluation.

After a brief hearing last year, the same judge ruled that Gilbert was fit for trial over his attorney’s objections.

The once-avid surfer is charged with murdering his father Gilbert Sr. in January 2015 after his dad slashed his $2,400 monthly allowance.

Gilbert Sr., 70, founded the hedge fund Wainscott Capital.