Your question does not provide enough information. Obviously, your injuries are serious and significant, so that a damage award could be substantial in order that it adequately compensate you for your pain and suffering IF those damages are due to negligence on the part of another. What your question fails to relate is WHAT CAUSED YOU TO FALL. You simply state that it was in daylight. This tells us that the fall was not due to inadequate lighting. Nothing in your question suggests negligence on the part of your friend (or, if he is possibly renting a unit where the deck stairs are part of the landlord's common area, his landlord). Unless you are suggesting that the condition of the stairs caused you to fall (either by their construction or by some condition existing at the time of your fall, for example), or some other behavior or action by some other party caused you to fall, you are not describing an event for which liability would attach. None of this is to mention the concern that unless your friend's deck stairs are the responsibility of a landlord, you would be making a claim against a friend and your friend's insurance company. If there is grounds to establish liability here, you need to be sure you are comfortable doing that. While this is exactly what insurance is for, and while your right to recover if your significant pain, suffering and disability is truly due to someone else's negligence should not be ignored at only your own expense, making a claim against a friend and his insurance is generally awkward in the extreme.
All of that being said, your injuries are serious, and you should make any decision on this with a full understanding of your rights. Contact a competent personal injury attorney in your area. Talk with them about the exact circumstances of your fall. He or she should be able to determine whether there is grounds for liability against any party which would warrant a claim. Even if you learn that you have no viable claim, it is better to explore your rights and to know where you stand.
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