There are three types of people in Ipswich, Massachusetts.

First, there are people who don’t use the parking lot at the train station because they have no use for a parking lot at the train station. They aren’t getting on the train; they’re not using the train to go to Boston or Newburyport or any point in between. This column is not about them.

This column is about people who use the parking lot at the train station.

Second, there are people who use the parking lot at the train station. They commute into Boston on weekdays (saving thousands a year on city parking fees); or they go shopping somewhere along the Newburyport line; or they promised their snotty little nephew they’d take him to the Science Museum, and they can’t put him off any longer.

Third, there are the outcasts, the riff-raff, the wretched refuse of humanity. You might use the term “low-life.” Or even “scumbags.” No, of course, nobody calls you by these names to your face, if you’re in Category 3.

But this is apparently the attitude of the town of Ipswich toward you.

In this third category are the folks who want to use the parking lot at the train station; they may even urgently need to use the parking lot at the train station, but they’re banned. Barred. Disqualified. Excluded. Forbidden. And that’s just the first six letters of the alphabet.

“Why?” You may ask.

What crime did these folks commit? What wrongdoing could possibly compel the town of Ipswich to go to the trouble of establishing actual legal barriers to keep these people from using the parking lot at the train station? Did these hooligans slash tires or spray graffiti on the benches?

No.

Did they park at an angle and use up two spaces? Wrong again. Don’t tell me they left an empty Zumi’s Macchiato cup on the platform!

None of these.

The only people the town of the Ipswich bars from parking on the parking lot at the train station are the people who want to park there overnight. Which means, by and large, people who work in Boston on the night shift. Those swine. Those no-good, dirty, rotten, graveyard-shift overnighters.

We’re talking maintenance workers. Cab drivers. Registered nurses. People who don’t have the common decency to get day jobs, so they can commute with the rest of us normal human beings.

I’m always interested in how underdogs get to be underdogs — this comes, perhaps from growing up in Chicago Cubs territory — so I summoned all my liberal courage and asked Ipswich Planning Director Glenn Gibbs why the town of Ipswich discriminates against night-time commuters. Glenn is a good friend of mine, a fellow Episcopalian and, as far as I’ve seen, a straight-shooter.

Also, he has announced his imminent retirement, so I felt reasonably sure that he wouldn’t take umbrage and pull strings at Town Hall to have me mercilessly persecuted.

Glenn was horrified. He had no idea. The very notion that parking is banned overnight on the parking lot at the train station was disturbing to him. He assured me he would check around with the proper authorities and report back to me to confirm. Overnight parking, he told me, must surely be allowed on the parking lot at the train station.

Uh, sorry, wrong.

“It appears that there is a ban on overnight parking at the MBTA lot after all,” his email said. “Its apparent purpose is to avoid the problem of parkers staying into the morning peak period and limiting the number of paces available for morning commuters.”

Yes, that’s quite a problem: Those damnable night-commuters not getting off their shifts and back on the train and into Ipswich station in time for the fine upstanding respectable daytime commuters to find their parking spaces.

So the Town of Ipswich said, in essence, “We’ll build a wall.”

I realized as I read Glenn’s email what a blessing it is that the town of Ipswich protects us from such a threat. A handful of parking spaces taken up by a few overnight commuters, when they’re needed by even the smallest percentage of our multitudinous daytime commuters, could devastate our local economy. Much wiser to force the overnight commuters to drive their cars into Boston, pay exorbitant parking rates, and live in relative poverty, so that the savings can go to the truly deserving: People who work in the daylight.

The acceptable people.

“This is an issue that our Downtown Parking Study Committee will be reviewing in the coming weeks,” Glenn added.

Well, OK, but I certainly hope that wisdom and justice will prevail, and those who are being rightly discriminated against will continue being discriminated against. Those graveyard shift losers need to know their place.

Sure, sure, I know what you’re thinking: This is a lawsuit waiting to happen. Any class of people unfairly prevented from accessing public services — they just hire a lawyer and off we go to court. But let’s not worry our pretty little heads. We can win this case. It’s entirely possible we’ll get a crooked judge.

Doug Brendel lives on outer Linebrook Road, far from the Ipswich train station. By the time he gets there, there’s hardly ever any place to park. Follow Doug at Outsidah.com.