A 40-foot cross in Bladensburg intended as a memorial to the World War I dead could shift the line between church and state in the U.S.

Last week, the Supreme Court heard arguments in Maryland-National Capital Park and Planning Commission v. American Humanist Association, a case brought by a secular humanist organization which wants the cross moved off public land.

Since 1971, the court has decided cases like this by asking three questions, known as the Lemon test: does the monument have a non-religious purpose, does it mostly advance a particular religion or does it excessively mix church and state.

Supporters of the Peace Cross argued that crosses have long been used in cemeteries to mark the dead and that the main purpose of the cross was to honor the war dead.

Critics, including the humanist group that brought the case, argued that a 40-foot cross in the middle of a well-trafficked intersection seems like an endorsement of Christianity.

But the court also considered another, deeper argument. With a conservative majority on the court, some saw a chance to throw out the Lemon test entirely and establish a much looser rule which would only stop the government from direct coercion of religion.

It is hard to determine what the justices may decide based only on the questions they asked in court, since these kinds of cases are often decided later behind closed doors. But observers said that Justices Neil Gorsuch and Brett Kavanaugh seemed receptive to overturning the precedent, while Chief Justice John Roberts worried about where to draw the line if they threw out the old test.

Whatever the court decides, the Bladensburg cross served as a powerful symbol of the debate over the line between church and state.