A Republican-backed House bill was introduced last week that calls for replacing Missouri’s “open” primaries with a “closed” system requiring voters to register with a particular party.

Missouri voters currently select the party ballot of their choice during primary elections, and can change parties from one election to the next.

House Bill No. 26, sponsored by state Rep. Dan Stacy, R-Blue Springs, would change the way in which Missourians register to vote.

Beginning Jan. 1, 2020, voter registration forms will include a choice of political party affiliations. For those already registered to vote, the proposed legislation will assign voters to a particular political party according to the ballot that was chosen during the 2020 presidential primary.

The bill goes on to read:

“Any registered voter affiliated with a political party shall remain affiliated with that political party for one year after any primary election before he or she may change party affiliation.”

The law would take effect for any primary held after Jan. 1, 2021.

Missouri currently utilizes an open primary system, in which registered voters do not have to be members of a party to vote in that party’s primary. A closed primary would eliminate “crossover” voting.

Twenty states have open primaries and 27 have closed or partially-closed primaries. California and Washington place all candidates on one ballot regardless of party and take the top two. Louisiana doesn’t hold primaries.