The court criticised the election board for its performance in last month's annulled presidential election and ordered a fresh vote to be held within 60 days.
Kenya's Supreme Court on Wednesday placed the blame for last month's annulled presidential vote firmly on the country's election committee, in its full ruling detailing the judges' decision.
Deputy chief justice Philomena Mwilu described "disturbing, if not startling, revelations" about the conduct of the Independent Elections and Boundaries Commission (IEBC) and singled it out for ignoring a Supreme Court order to open up its computer servers after opposition allegations of hacking.
"Our order of scrutiny was a golden opportunity for the IEBC to place before the court evidence to debunk the petitioner's claim," Mwilu read from the court's detailed judgement on Wednesday.
"If IEBC had nothing to hide it would have readily provided access to ICT (information and communications technology) logs and servers to disprove the petitioner's claim. But what did IEBC do with it? It contemptuously disobeyed the court orders in these very critical areas."
Lawyers for the National Super Alliance (NASA) coalition of opposition parties, led by Raila Odinga, last month challenged the re-election of President Uhuru Kenyatta, alleging rigging, hacking and tampering with results.
Chief Justice David Maraga declared the presidential election, and Kenyatta's victory, "invalid, null and void" on September 1.
Kenyan Chief Justice David Maraga said that during the election process some voting forms had no official stamps, signatures, serial numbers or even official watermarks.
Mwilu said that following the IEBC's refusal to comply with the court order, judges were left with no choice but to determine that the election commission's "ICT system was infiltrated and compromised and the data therein interfered with, or IEBC officials themselves interfered with the data, or it had bungled the transmission system and were unable to verify the data."
The election commission is due to hold a new presidential vote between Kenyatta and Odinga on October 17, but Wednesday's detailed ruling, plus opposition demands for an overhaul of the commission, have raised fears that it will be impossible to meet that deadline.