As judge (1856–1880)
In 1856, he became Chief Justice of the Common Pleas. He inherited the baronetcy in 1858. In 1859, Lord Campbell became Lord Chancellor, and Cockburn became Lord Chief Justice of the Queen's Bench.
Cockburn always sought out the most sensational cases and was astute in rearranging his diary so that he could sit in any trial likely to attract the attention of the press.
Several Prime Ministers offered to nominate Cockburn for a peerage, and he finally accepted the offer in 1864. However, Queen Victoria refused, noting that "this peerage has been more than once previously refused upon the ground of the notoriously bad moral character of the Chief Justice".
In 1875, the three English common law courts (the Queen's Bench, the Court of Common Pleas, and the Court of the Exchequer) merged to become divisions of the new High Court of Justice. The head of each court (Lord Chief Justice Cockburn, Chief Justice of the Common Pleas Lord Coleridge, and Chief Baron of the Exchequer Sir Fitzroy Kelly) continued in post. After the deaths of Kelly and Cockburn in 1880, the three divisions were merged into a single division, with Lord Coleridge as Lord Chief Justice of England.
Martin v. Mackonachie: Cockburn sitting in the Queen's Bench division granted a writ to quash Lord Penzance's suspension of Alexander Heriot Mackonochie from his clerical office for breach of the Public Worship Regulation Act 1874. Cockburn's decision was overturned by the Court of Appeal.
The Tichborne Case: Cockburn presided over the civil case in which Arthur Orton attempted to establish his identity as the missing baronet Sir Roger Tichborne. This trial collapsed after 103 days, the longest civil trial on record. Cockburn then presided over the subsequent trial of Orton for perjury, a famous trial that lasted 188 days, setting a record for criminal trials, of which Cockburn CJ's summing-up occupied eighteen.
R v. Hicklin: He developed the Hicklin test for obscenity.
The Alabama claims: He also played a role in the arbitration of the Alabama claims at Geneva in 1872, in which he represented the British government. He dissented from the majority view as to British liability for the actions of British-built privateer ships. He prepared the English translation of the arbitrators' award and published a controversial dissenting opinion in which he admitted British liability for the actions of the CSS Alabama, though not on the grounds given in the award, and discounted liability for the CSS Florida and CSS Shenandoah.
The Overend-Gurney fraud trial: the trial of the partners of Overend & Gurney, a bank that had collapsed in spectacular circumstances following precarious risks taken by the managers. In his summing up, Cockburn expressed the view that the defendants had been guilty of nothing more than "grave error".
Woodley v. Metropolitan District Railway Co.: Woodley was set to repair a wall in a darkened railway tunnel in which trains continued to run, without warning or dedicated lookout, and with barely sufficient clearance between train and wall for the workman to make himself safe when a train passed. Woodley was seriously injured when he reached across the rail for a tool and was struck by a passing train. Cockburn CJ held that the employer was not liable, invoking the principle of volenti non fit injuria.
Lavinia Ryves's claim to be the daughter of Prince Henry, Duke of Cumberland and Strathearn, a claim that ultimately failed after Cockburn CJ told the jury in summing up that Ryves's evidence comprised "outrages on all probability".
The trial of Michael Barrett for the Clerkenwell explosion.
The trial of Boulton and Park for transvestism and "conspiring and inciting persons to commit an unnatural offence".
The trial of Henry Wainwright for murder. The crime, in which Wainwright was arrested in possession of the dismembered body of his victim, was given more publicity at the time than those of Jack the Ripper.
The Eastbourne manslaughter
