He was highly praised by his contemporaries for his ability and integrity, but his reputation has suffered as a result of his conduct as a judge at the trial for treason of William Orr, which is widely regarded as a grave miscarriage of justice.
As he was generally agreed to be an able and conscientious judge, it was natural that Chamberlain should play a large part in the political trials of the mid-1790s, which culminated in the Irish Rebellion of 1798.
That he should be attacked by United Irishmen and nationalists generally was understandable; but one notable trial, that of William Orr, damaged his reputation even among his admirers.
[2] After the 1798 Rebellion he sat on the special commission to try the rebels, but the verdicts do not suggest that he displayed any great degree of severity: only five people were put on trial and only one was hanged.
Chamberlain conducted the trial with notable fairness: in his summing up he cast doubt on the evidence of O'Brien, and virtually directed an acquittal.
[2] John Philpot Curran, defending, exposed Wheately as a liar and a man of general bad character and argued that the jury had no choice but to acquit.
As it is generally accepted now that Orr was innocent,[2] Chamberlain clearly shares the responsibility for the miscarriage of justice; however, Avonmore was very much the senior judge and seems to have dominated the proceedings.
On the other hand, a Dublin newspaper, The Press, was sufficiently concerned by the trial to attack the conduct of both judges, and the editor, Peter Finnerty was prosecuted and convicted for seditious libel as a result.