Governor Mark Dayton threatened on Monday to veto the state’s bonding bill if it includes a change in the state building code requiring sprinklers in houses of a certain size. The bonding bill would remove that requirement

He is right to make that threat. The state building code isn’t a bonding issue and shouldn’t be included in the bonding bill. The state constitution tells the Legislature that it must limit bills to a single subject, a provision that has been violated innumerable times over the years.

The building industry feels that requiring new homes to have sprinklers will add a heavily to the cost of building a home. Attempts to derail the requirement haven’t been meeting with success, so someone has added it to the bonding bill, thinking it will be too important to veto.

That sort of shenanigan is forbidden by the constitution. The idea of requiring sprinklers in new housing may be excessive, but the way to address it is not to hide measure to block it in the state bonding bill.