Yes, everything depends on the level you are to in the appeals process. If this was an initial decision, and is approved, and the employer has requested a hearing, it is still in the early stages.
But still, if this is moving to the "hearing" stage, it should be fairly easy for you to go to your hearing and tell your side of it. No attorney should be necessary if you can express yourself clearly and concisely.
In a case of "voluntarily quit" versus "terminated for cause", where you won the initial decision, the employer will be presenting their evidence first that you voluntarily quit. (They cannot, at this point, introduce a lot of extraneous things like your attendance was poor or that they caught you stealing. Well, they could, but it would not be considered deeply. Why didn't they mention it before?)
Then you will be given an opportunity to speak, telling the hearing officer exactly what has been said when you were terminated, the situation under which you were told you were terminated, and presenting any written material you were given at the time of your termination, such as a separation letter or form. You may mention whether you had had any write ups or disciplinary actions taken against you previously for the reason you quit. In other words, did you know your job was in danger? Did you try to keep your job? Were you told specifically that you were terminated, or were you given the option to quit or be fired?
If you cannot comfortably afford an attorney, and you do not feel confident going into the hearing, you can talk to legal aid in your area. Usually they are very backed up, and it will draw out length that the procedure will take a bit.
But if you have already had the hearing, there is no need to retain an attorney at this point.If you are denied in the hearing, the next step is the "board of review" and as patty said, neither you or the employer is allowed to present much of anything new here. The case will be reviewed to make sure that the unemployment laws were followed.
Make sure you have been certifying for each week that has passed since you have filed your claim. If so, and the approval decision is upheld, you will be back paid for each week you have certified for. If you haven't certified, your claim would begin as soon as you started certifying.
Can you sue your employer for trying to keep you from receiving unemployment benefits, holding up the process or lying during a hearing? No.
Unemployment insurance is not a "needs based" program. You do not receive it based on how poor you are or how badly you need the money. You receive it based on your eligibility. And the employer has a right to present their case that you should not receive it, built right into the statutes. What they are doing is not harrassment or slander, it is exercising their appeal rights.