Use a soft, dry cloth to carefully rub at the dry paint. If the paint has recently dried, some of the paint may flake off as you rub it.
Read the furniture label to determine whether the leather piece is made of finished or unfinished leather. If the piece is unfinished, do not attempt to clean it yourself. Take it to a professional instead. However, finished leather is treated to repeal stains, so you can clean it yourself.
Place a small dot of dish detergent on a soft cloth, then add water to make it sudsy. Wipe the leather gently with the soapy cloth, rubbing carefully on the paint to loosen and remove it.
Dab a small dot of paint thinner on an inconspicuous area of the leather furniture to test its color safety, then allow it to dry completely. Rub the stain with a small amount of paint thinner if the leather retains its consistency and color after trying a test patch.
Use a store-bought leather cleaner, available at specialty furniture stores, if home remedies are ineffective. The manufacturer of your leather furniture may also offer a cleaning solvent that you can purchase at an additional cost.