Well, we have to assume that the Varon T had plenty of ammo left.
And even if none of the crew were going to go against Fajo, so what? Data could run the ship by himself enough to find the enterprise. And I'm sure he'd have a good chance of locking the crew up or incapacitating them somehow. He's still got a deadly weapon, remember, which works perfectly well for a threat.
So I stand by my claim that there was absolutely NO justification for Data to try to kill Fajo.
Except that Fajo deserved it. He's a murderer, a kidnapper and a theif who existed outside of Federation jurisdiction for a long time and Data had no clue whether they would ever catch up to him.
Rubbish.
First of all, the Federation doesn't have the death penalty anymore (unless Fajo has gone to the Talos Star Group, which I doubt).
Secondly, even if he did deserve the death penalty, would Data do it himself or would he make sure that Fajo was tried by a jury? Data never seemed to be the type to dispense summary justice.
Thirdly, Data had the means to contain Fajo! I've explained this many times.