He was made a commissioner along with Roger Mortimer to investigate certain grievances of the Oxford scholars, and in 1278 acted as an itinerant justice in Hertfordshire and Kent.

He was also one of the four negotiators selected in 1289 by King Edward I of England to treat at Salisbury with the Scottish and Norwegian envoys about sending Margaret of Norway to Scotland.

Giffard was engaged in many disputes with his monastic cathedral chapter, long accounts of which, written from the monks' point of view, have survived in the "Annals of Worcester".

In the end Giffard was glad to compromise the case, and received a grant of land at Knightwick and agreed not to visit Malvern as his predecessors had done and Ledbury was restored.

Giffard had already been involved, like the other suffragans to Canterbury, in the struggle against Peckham's excessive claims of metropolitical jurisdiction; he however later more friendly with him, and sent the Archbishop many expensive gifts.

In 1301, William of Gloucester produced thirty-six articles against him before the Archbishop; although mostly small, technical and legal, they included: Both complaints were well investigated, and the Bishop's answers are recorded along with the charges in his register.

Giffard died on Friday 26 January 1302,[4] and was buried on 4 February by John de Monmouth, Bishop of Llandaff, in Worcester Cathedral, on the south side of the altar of the lady chapel; his tomb remains there still.

Under the terms of Giffard's will, which was dated 13 September 1300, he left a large number of legacies to his kinsfolk, including his sister Mabel, Abbess of Shaftesbury, and to various churches.