It's evidence of a minimum viable standard for rule of law. Take, for example, Barbados, which is dependent on foreign tourism and foreign investment. If you a

It's evidence of a minimum viable standard for rule of law. Take, for example, Barbados, which is dependent on foreign tourism and foreign investment. If you are going to invest in Barbados, you'd like to know that your property rights will be respected, that contracts will be honored, and that there will be due process in case there is a dispute. Being a commonwealth nation is one of the things that helps sway that in your favor, particularly for small island nations, primarily due to the British history of respect for property, English common law (which is less amenable to be changed by fiat), and an impartial judiciary. Obviously that's not the only thing you'd look at, but it's one of the things you'd take into account. On the other hand if you are a major nation like Australia it doesn't matter. But if you are an island like Barbados, you need all the help you can get to demonstrate to investors that their investment will not be confiscated the next time some populist comes to power.