Speak with Odar in Oradam Village to start this mission. This is a level 7 quest.

Odar: You! Get away from me... you did this to me! Dirty soldiers... beating an old man, stealing his daughter.

You can tell him:
Those men should be arrested
It wasn't me
I'm sure you deserved it

Choose the first option to tell him that they were criminals, not good soldiers. He asks you to help him, and not to turn a blind eye like the rest. His daughter means everything to him. He begs you to help him get his daughter back.

You can say:
Why did they do this?
Where did they take her?
Forget it.

If you choose the first option, you tell him that you do not understand why soldiers would take your daughter. Where would they take her? He tells you that there has been a string of abductions lately. But he never thought they'd take his Qo'el. They were headed towards the fort.

Check your mission log:

Hail the Liberators
Odar's daugher, Qo'el, was kidnapped by Republic soldiers and taken to Fort Garnik. You have agreed to investigate her disappearance. Head to Fort Garnik and search for Odar's daughter.

Your task is to find Odar's daughter. Take the speeder back to Fort Garnik, and open your map to locate the Interrogation center where Qo'el is held. Kellik and another soldier are torturing her for information, even though she denies knowing anything. Kellik sees you come in and tells you that you are not allowed in here, this is a top secret operation.

SWTOR Hail the Liberators

You can tell him:
What's all this?
Sorry
I'm investigating a beating

Try the third option and ask them if they attacked a merchant. Qo'el begs you to stop them. But they accuse her of being a traitor to the Republic and thus deserves what she gets. The courts are full and so justice needs a little help, even if that means Republic soldiers have to twist a few arms. Torture is a legitimate tool of warfare. Do you think the separatists won't use it? Do you think the Empire won't use it? These wretchers have been caught, every last one of them, doing work for the separatists. They are traitors, and more importantly, they have information on separatists movements. All the soldiers are doing is coaxing the information out of them, info that will save so many Republic and Mantellian life. Who'll care how they got that information?

You can respond:
Me
Bribe me
We're better then this

Choose the first option to express that this is not acceptable to you and you will make sure their superiors care too. Kellik asks you to take a ring back to the girl's daddy and tell him it's all you could find of her. The ring's got a listening device in it and they will be able to gather all the evidence they need without resorting to these unsavory means. You have to decide:
Will do [DARK]
Absolutely not [LIGHT]

If you choose the first option, you get 50 dark points. You tell him you will return to the merchant and plant the bug. Qo'el protests and accuses you of being cruel, corrupt, and selfish. This is why the separatists endure. Go back to Odar. Tell him you got there too late. She asked you to give him her ring before she died. Express your condolences. He is sad but at least he knows what happens (or so he thinks). You get credits and experience and a piece of green armor as your reward.

If you choose the second option, you tell them the charade of justice ends now and you gain 50 light points. You draw your gun, but they are not interested in a shoot out. They let her go. You remove the shackles off her and tell her to go home to her father. She says she will call him by holo and let him now he's ok, that you saved her. It seems like it's nothing but corruption on Ord Mantell these days, good to know you're an exception. Tell her to be careful from now on. Return to Odar in Oradam Village. He thanks you for saving his daughter. You get credits, experience, a stim, and a green armor piece as a reward.

This completes the mission "Hail the Liberators".