Primary Voters in New York May Be Hobbled

The most commonly-cited reason for [Sanders supporters'] disenfranchisement was that they'd registered as unaffiliated voters, then missed the deadline to change their enrollment to Democratic for the purpose of voting in the presidential primary.

[...]

Section 5-304 of New York election law provides that the deadline for voters to apply for a change in party enrollment is 25 days before a year's general election, which means that for the purposes of the 2016 presidential primary, the deadline to switch registration to one or another party was October 9, 2015. Over six months ago. (New York's "closed primary" system restricts participation in primaries to officially-designated party members.) Fortunately for party bosses who delight in this onerousness, given that it tends to depress turnout and therefore entrench their grip on power, the U.S. Supreme Court upheld the constitutionality of the law back in 1973.

[...]

"It is clear that preservation of the integrity of the electoral process is a legitimate and valid state goal," the court reasoned, rationalizing the early enrollment deadline on the basis that it serves to prevent the phantom phenomenon of "raiding," i.e. groundswells of people registering for a party with the cynical intent of mucking around with their rivals' candidate-selection procedure.

[...]

The majority on the court seemed to conflate what is best for political parties with what is best for the electorate writ large.

  NY Daily News

Gee, what a surprise.

...but hey, do what you want...you will anyway.