Ashraf shot dead his 18-year old daughter Saba, son-in-law Karamat and the bridegroom’s father Ikram after his daughter solemnized her marriage without his consent.
The accused arrested shortly after committing the crime.
Ashraf, in his confession statement, said that he first took the life of his daughter and son-in-law for their love marriage and then went on to claim the life of Ikram for assisting them.
Saba had married to Karamat with her free will 18 months ago and had returned home recently.
A similar incident took place on Wednesday in the country’s cultural capital when Zeenat Bibi was set on fire after she wed 20-year-old motorcycle mechanic Hasan Khan against the wishes of her family.
Her mother Perveen Bibi has admitted to the killing, though details of the brutal murder remain unclear.
Pakistan had amended its criminal code in 2005 to prevent men who kill female relatives escaping punishment by pardoning themselves as an “heir” of the victim.
But it is left to a judge’s discretion to decide whether to impose a prison sentence when other relatives of the victim forgive the killer — a loophole which critics say is still exploited.