False. In Texas a pardon can only be given after a recommendation from the parole board, which reviewed the evidence and unanimously recommended the pardon.
He appointed the parole board. He wanted this done before the guy was even sentenced.

“Texas has one of the strongest ‘Stand Your Ground’ laws of self-defense that cannot be nullified by a jury or a progressive District Attorney. I thank the Board for its thorough investigation, and I approve their pardon recommendation,” Abbott said.
He is saying if he feels it was self-defense it does not matter what the jury says. What country is this guy from, Russia? Do you actually want to be taking this nutjobs side?
ETA: Just to show what a lunatic this Gov is they also restored his gun rights so he can murder again!!!
Lets also not forget the fact that this guy is a known racist.