In addition, Charles Edward Pickett Jr. was charged with four counts of operating a vehicle while intoxicated causing serious injury related to four additional cyclists who were hurt in the same June 7 car crash, bringing to 14 the total number of charges against him.
Getting said Pickett was under the influence of a controlled substance at the time of the crash. He did not elaborate.
The cyclists were struck along the shoulder of a road in Cooper Township, 45 miles (72 km) south of Grand Rapids, Michigan. Five of the cyclists were pronounced dead at the scene.
Pickett, 50, was originally charged with five counts of second-degree murder and four counts of reckless driving. He faces life in prison on each murder charge. Getting told a news conference that four of the charges announced on Wednesday would replace the four reckless driving charges.
A judge on Wednesday ordered Pickett to undergo a competency exam at the request of his attorney. A preliminary hearing that was scheduled for later this month has been postponed as a result.
An attorney for Pickett could not immediately be reached.