As far as I'm concerned you can't manipulate minds in a full deal thus you cannot forcibly change their opinion about something. Sorry to dissatisfy
However there are various things you can do in order to protect that person and prevent them from being put in jail...
- Cast a protection spell upon them, whichever form you choose. I specifically recommend making an amulet or a bag which includes the following protective stones / symbolism :
Obsidian - this stone is considered to be a very protective stone which also happens to be a grounding stone. It can be a very great addition to the bag you're going to make. This is good for you since it's going to banish and back of any negative energy that floats around or is sent in a specific moment.
Iron- I recommend adding some iron because it's considered to be protective. I am also into Astrology and I can tell you that this stone is related with the planet Mars which can be an advantage for you if astrology represents something which is more that merely symbolic. In case iron is a though thing to work with for you, you may use some gemstones that contain irons and are good for protections such as: Bloodstone, Hematite, Tiger Eye, etc... These gemstones are very recommended to be added to what you're going to make while the also contain iron which, as I said is very recommended as a protective item !
Any specific sigils or protective symbols you may find- runes, sigils, symbols are really recommended to carve on something while dealing with protective work. I specifically recommend you carving some runes especially the rune Tiwaz (Tyr). Something better that I've heard of is anticlockwise spirals which is fairly neat as a use of protective rune and symbol.
On a side note you can either make a small bag with a red ribbon and either make an amulet which may be less comfortable. Let her carry this in special events...
- Pray for it. Praying to the existence of higher form of power which you specifically believe in is always highly recommended whenever you're in trouble and need a divine assistance while your intentions are clear and reasonable. Praying is always helpful and it happens to be a great vote of confidence.
- Getting a luck charm or casting any sort of a luck spell might be helpful in your case. I don't really have any specific recommendations so use whatever you'd like to use as you find it useful. However I believe you can freely choose to use the following herbs that happen to obtain properties that are specifically associated with protection and sometimes with luck as well:
Ague Root, Angelica, Ash Leaves, Barley, Basil, Betony, Buckwheat Flour, Burdock, Chamomile, Chili Pepper, Dragon's Blood, Grain, Ivy, Mustard Seed, Tumeric.
You can either cast a spell using the following herbs and either make a powder out of them and design it for your use (Scattering herbs and powders is a common way of invoking the influence of the herbs to achieve your magical intent).
Hope it helps.