I think it was botched. I don’t really want to torture even the guilty. I just want them cleanly executed. My solution? A heavy sedative, and then a heroin overdose. Simple, and effective. Done and gone! Shoulda been done to Manson many years ago. Do it quick and clean. Just get rid of them!
That's what they did:
"a lethal injection with a combination of the sedative midazolam and the painkiller hydromorphone."