Firing into a mixed group of enemies and allies is always a situation you should avoid if possible. Because you just know what's going to happen.
(Unless of course your shooters have semi-mystical or legendary level training. And the game style is highly cinematic. And the GM is feeling really generous.)
Transcript
GM: The Ewocs fire a massed volley of arrows at the Imperial troops.
Chewbacca: But we're right in the middle of them.
Leia: And they're wearing armour. And we're not.
Han: It'll be fine. We evade!
GM: No need. The Ewoc arrows all hit troopers, and none hit any of you.
R2-D2: That's statistically... improbable.
C-3PO: Not if they've been trained by you-know-who.
Han: I grab a blaster!
GM: You're surrounded by troopers.
Han: I grab a trooper!
Clone Trooper: Hey! Let me go!
Han: I throw him at another trooper.
Clone Trooper: Thank yooooou!
[SFX]: THUD!!