The pupil transportation industry has been making strong efforts to deter school bus stop-arm law violators, but what are we doing to deter school bus trespassing law violators?

Stop-arm running may be the more dangerous violation — there were six student fatalities from stop-arm running reported in the latest school year on record, 2010-11. But school bus trespassing certainly also carries a high degree of risk to students as well as to drivers. That was tragically illustrated when an armed intruder fatally shot school bus driver Charles Poland and kidnapped a 5-year-old boy in Midland City, Ala., in January.

We’ve come across other recent reports of school bus trespassing attacks. Here are a few more examples:

• In October, in Toms River, N.J., a woman allegedly boarded a school bus and slapped a 9-year-old boy. The Ocean Signal reported that the boy’s head hit a window, and he required treatment at a hospital.

The woman, Rebecca Sardoni, said that her daughter had been the victim of bullying. However, she apparently took revenge on the wrong child — officials said that the 9-year-old whom Sardoni allegedly slapped was not involved in the bullying.

Sardoni was arrested and charged with simple assault, criminal trespass and terroristic threats.

• In December, a 38-year-old woman in Macon, Ga., was sentenced for boarding a school bus and attacking her 11-year-old cousin in April 2012.

The Telegraph reported that a judge ordered the woman, Natasha Freeman, to wear a sign proclaiming “I made a fool out of myself on a Bibb County Public Schools bus” for a week at a bus stop. Her sentence also included helping to wash a bus, serving five years on probation and paying $500 in attorney fees.

The “fool” sign may not become a common punishment (although you may recall that an Ohio woman got a similar sign duty for driving on a sidewalk around a stopped bus last year). But it is clear that substantial penalties are needed to help deter school bus trespassing.

Alabama recently passed the Charles “Chuck” Poland Jr. Act, under which school bus trespassing is a Class A misdemeanor and could result in jail time.

State pupil transportation director Joe Lightsey said that unauthorized entry on Alabama school buses has increased dramatically in recent years, but existing trespass laws did not specifically address the unauthorized entry of a school bus.

As with stop-arm running, an important component in any campaign against school bus trespassing is public awareness. Parents and others need to know that they are prohibited from boarding the bus.

In some places, school buses have signs posted by the service door that warn against trespassing, even citing a specific state code. Drivers can refer to the sign if an unauthorized person tries to enter.

In many of these trespassing incidents, an angry parent is responding to a problem that his or her child experienced on the bus, such as bullying.

Accordingly, all parents need to be informed and occasionally reminded that they should address such matters with the school or transportation office — not on a bus full of children.