Yes you can sue. It is likely to be a small case unless there is a severe injury not described in the question. It theoretically punitive damages may be available against the guard, however, with out some one to testify that they witnessed you being intentional abused it will be very hard. Settlement offers are likely to be in the nuance range.
Ask the casino to pay for your medical expenses. You can also ask for damages for pain and suffering. As Howard suggests, you should consult with an attorney. Most personal injury attorneys will provide a free consultation. If your injury occurred on tribal land, you will need to speak with an attorney licensed to practice with that particular tribe.
Legal Disclaimer: I am not your attorney. The only method of establishing an attorney--client relationship with me is by a retainer and fee agreement signed by me, which is not offered via this site. The information given is not legal advice and is for general information only. My answer is limited to the facts presented and may not be complete or applicable to your situation. My answer is given upon the condition that you will contact an attorney licensed in your state to receive legal advice that applies to your particular situation.
It depends upon the details of what was happening, did the guard push you out of the way of a knife welding manic, or does he like beating up on people like you. There will probably be a video, so write to the casino and tell them to save. Whether the casino or guard is labial is only half the equation. The second big variable is how badly you have been hurt. If the answer is I am sore, let it go, if you have been injured in a serous way there may be something there. See your doctor and tell him about your injury’s. In Nevada there is a two year statute of limitations.
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