The Lord O'Brien | |
|---|---|
 Lord O'Brien. | |
| Lord Chief Justice of Ireland | |
| In office 1889–1913 | |
| Monarchs | Victoria Edward VII George V |
| Preceded by | Sir Michael Morris, Bt |
| Succeeded by | Richard Robert Cherry |
| Personal details | |
| Born | 29 June 1842 Carnelly House, Clarecastle, County Clare |
| Died | 7 September 1914 (aged 72) Airfield, Stillorgan, County Dublin |
| Nationality | Irish |
| Alma mater | Trinity College Dublin |
Peter O'Brien, 1st Baron O'Brien, PC, QC (29 June 1842 – 7 September 1914), known as Sir Peter O'Brien, Bt, between 1891 and 1900, was an Irish lawyer and judge. He served as Lord Chief Justice of Ireland between 1889 and 1913. In his lifetime he was universally known as Peter the Packer, due to the skill he displayed as Attorney-General in securing verdicts by packed juries.