The new guidelines also are more in line with laws in 43 states and the District of Columbia that require youth and high-school athletes to be removed from play and to return only after at least 24 hours and with the permission of a health-care professional.

WSJ: Tougher Rules Advised for Athletes After Concussion

"We introduced rules on unacceptable conduct last season, in line with the laws of the land, " a spokesman said.

BBC: SFA vows to tackle 'Famine song'

For advice on rewriting your will in line with the new federal estate and gift tax laws, click here.

FORBES: Your Parents As Beneficiaries Of Your Estate?

But, in practice, since new drink-driving laws came into force in Japan last June, courts are taking a tougher line with passengers as well as drivers.

ECONOMIST: New laws on drink and smoking