The criminal justice system is being brought to its knees because SA's two main criminal forensic science laboratories have been unable to process DNA and other evidence for almost a year.

Thousands of blood, semen and other DNA samples are piling up at the two SAPS laboratories in Cape Town and Pretoria due to a funding and supply chain crisis which has left them without essential chemicals, consumables or service contracts.

Some 28,000 samples have piled up over an 11-month period in Cape Town because it is not being supplied with the essentials, SAPS chief forensic analyst Lt-Col Sharlene Otto said in the high court in Makhanda, Eastern Cape, on Tuesday.

Cape Town services the Western, Eastern and Northern Cape. Otto was summonsed to give evidence under oath about the year-long delay of DNA evidence analysis in two separate cases of child rape set down to be heard in the same court.

Most court cases, particularly rape cases, can often not proceed without DNA evidence.

The crisis is directly contrary to President Cyril Ramaphosa's recent promise that government would capacitate the criminal justice system in its fight against the rape scourge.