From Ditewig’s 101 Questions and Answers on Deacons:Canon law …] states that a married man may be ordained a deacon at age thirty-five; an un-married man may be ordained at age twenty-five. However, the USCCB has decided that *all *candidates for the permanent diaconate should be thirty-five. The local bishop can waive one year from this requirement, and if the bishop would like to ordain someone even younger than thirty-four, he may request authority to do so from the Holy See.
The specific canon he’s referring to is canon 1031 in the CIC.
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