Now we know: Corruption and allegations of criminal wrongdoing matter. They turn off voters and have a devastatingly chilling effect on the democratic process. That is one indisputable message from Tuesday’s Democratic primary in the District.

D.C. Council member Muriel Bowser (Ward 4) may have won the Democratic Party mayoral nomination. But none of us should celebrate the fact that only 22.5 percent of 369,037 registered Democrats went to the polls. That turnout for a regular primary may be one of the lowest in decades. Consider that 37 percent of Democrats voted in the 2010 primary.

Bowser snagged 44 percent of the vote. That number is misleading though. She actually received only 35,899 votes.

“This is the saddest election I’ve seen in a long time,” lamented Njeri Santana, who, accompanied by her 12-year-old son, voted at Precinct 19 at Dunbar High School.

It’s hard to fathom that D.C. residents, who decry their lack of representation in Congress, would be so cavalier about voting. Equally important, the D.C. Democratic State Committee’s growing inability to inspire its members to participate in the electoral system argues that it has a major problem and that a leadership change is desperately needed. Its only saving grace may be that other political groups, including the Republicans, are just as lackluster and face similar challenges.

“It’s like people have forgotten how the right to vote was won,” said Phoebe Dixon, a poll worker.

Some observers blamed Tuesday’s depressed turnout on the shift in the primary date from September to April 1, which caught many residents unaware. Others cited the bad weather — days upon days of snow, sleet and icy rain, even as recently as Sunday.

Don’t believe the rationalizations. Most of the people with whom I spoke pointed the finger at corruption. “Folks have corruption fatigue,” said Greg Rhett, a Ward 7 resident.

That disease took hold of the District electorate in 2011, just weeks after Gray was sworn into office, when fringe mayoral candidate Sulaimon Brown revealed he had been paid cash by Gray’s campaign to trash incumbent Adrian M. Fenty during the 2010 primary. Meanwhile, two D.C. Council members — Harry Thomas Jr. and Kwame Brown — pleaded guilty to unrelated federal felonies. Things went from bad to worse when Jeanne Clarke Harris disclosed the details of a shadow campaign. And then just a week before early primary voting began, businessman and campaign financier Jeffrey E. Thompson said in open court that he provided nearly $700,000 for that effort and that Gray knew all about the illegal operation.

Those accusations not only took wind out of the incumbent’s campaign, they also were a body blow to democracy, stealing voter confidence and leaving many wondering who and what to believe. “At this point, people just aren’t sure who to trust,” said Rhett. It certainly didn’t help when Gray’s own lawyer said he expected the mayor to be indicted.

Election after election, people have been selecting individuals they believed would be good leaders. Now, said Eugene DeWitt Kinlow, host of WPFW-FM radio’s D.C. politics show, they think they have made bad decisions. “People were worried that there is a chance that despite their best effort, it could all backfire on them, again.” The antidote: Sit it all out.

That, said former council candidate Sekou Biddle, who was working a poll in Ward 4, was the wrong answer. “We need people to be more involved.”

That may not happen, however, until there has been a clean sweep of corrupt politicians in the city, and the primary is opened to all voters — regardless of party. But don’t bet on that happening anytime soon. Democrats like winning the easy way.