Shama Masih, 24 and five months pregnant at the time, and her husband Shahzad Masih, 26, were beaten by an angry mob and thrown alive into a burning brick kiln in Kot Radha Kishan in Punjab province in November 2014.
It's after allegations they blasphemed against the Quran whilst working as labourers at the site.
The British Pakistani Christian Association (BPCA) has said while more than 100 people have been arrested since Shama and Shahzad's murders, no one has been convicted.
The brick kiln owner who originally brought the blasphemy claims against the couple has also walked free.
The BPCA has been providing support for the couple's surviving children. The Pakistani government has officially awarded the children compensation but it cannot be accessed until they're 18.
A service (below) remembering two years since Shama and Shahzad's deaths was held in Kot Radha Kishan recently.
Wilson Chowdhry, from the BPCA, told Premier: "It's extremely disappointing. The impunity with which attacks on Christian communities occur, where the perpetrators simply get off, is ridiculous.
"Something seriously has to be done to speed up the court process but also to ensure safety for witnesses who could convict criminals.
"When the main perpetrator is released it does only give us a slither of hope that any convictions will come to fruition.
"Like many instances where Christians have been attacked, all of these individuals will be exonerated and sadly, justice again, will be overlooked."
Listen to Premier's Aaron James speaking to Wilson Chowdhry:
