Hi
I've checked the standard reference works:
(1)
Jim Herlihy, The Dublin Metropolitan Police: A complete Alphabetical List of Officers and Men , 1836-1925.
Noting found for John Pearce or similar
(2)
Jim Herlihy, The Royal Irish Constabulary: A complete Alphabetical List of Officers and Men , 1816-1922.
Entries found:
John Pearce, Service No. 75456
William John Pearse, Service No. 69886
The service no. for John Pearce corresponds to an entry date to the force of Oct-Dec 1920 - much too late for the man of interest. The Pearse entry corresponds to Feb-Apr 1920.
Not promising, unfortunately. Perhaps he was a constable in England ?
regards
Gerry