Today the Supreme Court ruled that a heterosexual couple can enter a civil partnership. Rachael Griffin, tax and financial planning expert at Old Mutual Wealth, says this leaves the door open for other duos, such as siblings, to argue they are being discriminated against if they cannot enter a civil partnership.Civil partnerships, like marriages, offer legal and financial protection for both parties in the event of the relationship ending and benefits including inheritance, tax, pensions and next-of-kin arrangements.