TOWSON, Md. – I didn’t want to do it.

I didn’t want to spend a day in the jury assembly room of the Baltimore County courthouse worrying about whether I’d get selected for a trial that might keep me there several more days.

But the summons I received ordered me to show up for jury duty the morning after Memorial Day.

Jury service on a criminal or civil trial is one of the few things government requires of people in our democracy. Not military service. Not community service. Not even high school graduation.

Most states choose potential jurors from voter registration and driver’s license rolls. Whatever the selection process, large numbers of Americans see jury duty as an inconvenience. And many simply don’t show up.

In some jurisdictions around the nation, the number of jury no-shows has reached epidemic levels, USA TODAY reported last year. Fifty-two percent of those summoned to jury duty in Marion County, Ind., didn’t show up in 2006. Also that year, more than three-quarters of would-be jurors in Dallas County, Texas, were no-shows, according to the Dallas Morning News.

Between 2001 and 2005, roughly 64 percent of people summoned for jury duty in Pasco County, Fla., were excused from jury duty or didn’t bother to appear, the Tampa Tribune reported last year.

I didn’t want to show up when I received my summons, but I did. And others should, too.

Jury duty is an important lesson in civics. It’s a door into our justice system that separates us from countries where despots run trials by fiat. More than anything else, this country’s jury system gives citizens a chance to put their hands on the throttle of our democracy – and makes us participants in one of the most important freedoms we enjoy.

The jury pool I was part of numbered 83 people. They were young and old, black and white. A few were law enforcement officers. Many were crime victims themselves. All seemed to take their jury service quite seriously.

At one point during the day, our pool was sent to a courtroom for a rape trial. The defendant was a reed-thin, freshly minted Marine Corps private. He was charged with raping a young woman on New Year’s Day.

This baby-faced young man and the woman he allegedly raped deserve the best justice a court can offer – as do victims and defendants in all criminal cases. But given how often people duck jury duty, you have to wonder whether these scofflaws are tilting the scales of justice out of balance.

As the judge in the rape case questioned us about our fitness for jury service, I thought about my initial reluctance to show up and how that compared with the need for the defendant and his accuser to get a fair trial.

As it turned out, I wasn’t one of the jurors seated in that case. But as I listened to Judge Lawrence Daniels talk about the important role jurors play in the nation’s judicial system, I wish I had been.

Jury duty, like military service, is a real act of patriotism.

Many Americans are unwilling to spend several years of their life in the armed forces, but it’s hard to imagine why so many would refuse to perform a short stint on jury duty.

“I consider trial by jury as the only anchor ever yet imagined by man, by which government can be held to the principles of its constitution,” Thomas Jefferson once said.

That’s as true today as it was when Jefferson uttered those words.

Freedom is like a muscle. The more you use it, the stronger it gets. Leaving it unused will weaken our democracy beyond repair.

Jury duty is a guard against this kind of atrophy.