As Lord Keeper, Egerton's judgements were admired, but Common-law judges often resented him reversing their decisions.
He also attempted to expand the jurisdiction of the Court of Chancery to include the imposition of fines to enforce his injunctions.
In the 9th Parliament of the reign of Elizabeth (1597–1598) he supported legal reform and the royal power to create monopolies.

Sir Thomas was a friend of Robert Devereux, 2nd Earl of Essex, and often interceded to mend relations between Essex and the Queen.
After Essex returned from Ireland in disgrace he was placed in the Lord Keeper's custody, under house arrest at York House, Strand.
He was one of the judges at Essex's first trial, and tried to persuade him to apologise and beg mercy from the Queen.
He pronounced the sentence against Essex, although it was dictated by the Queen.
During Essex's rebellion, he was sent to persuade Essex to surrender, but was instead held hostage for several hours until one of Essex's supporters freed him to gain pardon from the Queen.

Egerton bought a house at Harefield and in August 1602 staged an elaborate entertainment for the queen.
When James VI of Scotland succeeded to the throne of England as James I he kept Egerton in office, and made him Lord Chancellor and 1st Baron Ellesmere on 19 July 1603.
He was removed from the office of Master of the Rolls on 18 May 1603, but as the office was granted to an absentee Scottish Lord he continued to perform its duties.
 Shortly afterwards he presided over the trial of Barons Cobham and Grey de Wilton for high treason for their part in the Main Plot.

In the first Parliament of James I Lord Ellesmere attempted to exercise the right of the Lord Chancellor to disqualify members from sitting in the House of Commons, but in the end yielded that right to the House itself.
He attempted to persuade Parliament to support the King's plans for a union of England and Scotland, but was unsuccessful.
In 1606 he ruled that Scottish subjects born after the succession of James I were naturalised English subjects.

Lord Ellesmere supported the Royal Prerogative, but was concerned to define it, and ensure it was never confused with the ordinary legal processes.
Towards the end of his life, he stood out against the arguments made by Sir Edward Coke, the Lord Chief Justice, and ultimately aided the King in securing his dismissal.
He attempted to resign several times after this, as he became increasingly old and infirm, and the King finally accepted his resignation on 5 March 1617, after creation as Viscount Brackley on 7 November 1616.
He was promised the earldom of Bridgewater, but showed little interest, and died twelve days after leaving office on 15 March 1617.
 He is buried in Dodleston, Cheshire.
As Lord Keeper, Egerton's judgements were admired, but Common-law judges often resented him reversing their decisions. He also attempted to expand the jurisdiction of the Court of Chancery to include the imposition of fines to enforce his injunctions. In the 9th Parliament of the reign of Elizabeth (1597–1598) he supported legal reform and the royal power to create monopolies.
Sir Thomas was a friend of Robert Devereux, 2nd Earl of Essex, and often interceded to mend relations between Essex and the Queen. After Essex returned from Ireland in disgrace he was placed in the Lord Keeper's custody, under house arrest at York House, Strand. He was one of the judges at Essex's first trial, and tried to persuade him to apologise and beg mercy from the Queen. He pronounced the sentence against Essex, although it was dictated by the Queen. During Essex's rebellion, he was sent to persuade Essex to surrender, but was instead held hostage for several hours until one of Essex's supporters freed him to gain pardon from the Queen. 
Egerton bought a house at Harefield and in August 1602 staged an elaborate entertainment for the queen. When James VI of Scotland succeeded to the throne of England as James I he kept Egerton in office, and made him Lord Chancellor and 1st Baron Ellesmere on 19 July 1603. He was removed from the office of Master of the Rolls on 18 May 1603, but as the office was granted to an absentee Scottish Lord he continued to perform its duties.  Shortly afterwards he presided over the trial of Barons Cobham and Grey de Wilton for high treason for their part in the Main Plot.
In the first Parliament of James I Lord Ellesmere attempted to exercise the right of the Lord Chancellor to disqualify members from sitting in the House of Commons, but in the end yielded that right to the House itself. He attempted to persuade Parliament to support the King's plans for a union of England and Scotland, but was unsuccessful. In 1606 he ruled that Scottish subjects born after the succession of James I were naturalised English subjects.
Lord Ellesmere supported the Royal Prerogative, but was concerned to define it, and ensure it was never confused with the ordinary legal processes. Towards the end of his life, he stood out against the arguments made by Sir Edward Coke, the Lord Chief Justice, and ultimately aided the King in securing his dismissal. He attempted to resign several times after this, as he became increasingly old and infirm, and the King finally accepted his resignation on 5 March 1617, after creation as Viscount Brackley on 7 November 1616. He was promised the earldom of Bridgewater, but showed little interest, and died twelve days after leaving office on 15 March 1617.  He is buried in Dodleston, Cheshire.
Thomas Egerton, 1st Viscount Brackley