IIRC the Tennessee Legislature Made Pi = 3.2 Exactly

If not, it's a suburban legend too good not to pass on¹...

Anyway, it did about as much good as the US Congress declaring a goal for cellulosic biofuels:

U.S. unlikely to hit Renewable Fuel Standard for cellulosic biofuels

The Renewable Fuel Standard requires that 15 billion gallons of corn-based ethanol, 1 billion gallons of biodiesel and 16 billion gallons of cellulosic fuels be produced annually by 2022. According to the report, the corn ethanol numbers and biodiesel can be achieved, but the cellulosic goals probably cannot.

Some things are just not amenable to legislation.

¹ It wasn't Tennessee, it was Indiana, and the bill did not pass:

It happened in Indiana. Although the attempt to legislate pi was ultimately unsuccessful, it did come pretty close. In 1897 Representative T.I. Record of Posen county introduced House Bill #246 in the Indiana House of Representatives. The bill, based on the work of a physician and amateur mathematician named Edward J. Goodwin (Edwin in some accounts), suggests not one but three numbers for pi, among them 3.2, as we shall see. The punishment for unbelievers I have not been able to learn, but I place no credence in the rumor that you had to spend the rest of your natural life in Indiana.