The attack on a transgender woman in a Rosedale McDonald's has led to widespread condemnation of her assailants and bewilderment at the inaction of bystanders — including a (now former) McDonald's employee who videotaped the whole incident. But the question of whether the attack should result in hate crime charges has proved more divisive.

Gay and transgender rights activists and the victim herself, Chrissy Lee Polis, say it should clearly be considered one, and a Baltimore County grand jury agreed, this week indicting an 18-year-old suspect, Teonna Brown, on charges that could add 10 years to the penalties she faces for assault. But as often occurs in hate crime cases, the incident has caused others to question why some crimes should be punished more harshly than others based on the attitudes and motivations of the perpetrators. After all, isn't every assault motivated, in a sense, by hate?

The evidence is yet to be heard in this case, so it is impossible to know whether a jury will conclude that this attack meets the legal definition for a hate crime. But it is worth reaffirming the importance of hate crime statutes and the legal basis for them. Maryland law prescribes greater penalties for crimes motivated by the victim's race, color, religious beliefs, sexual orientation, gender, disability, national origin or (in a recent addition to state law) because that person is homeless. It does so not because members of some groups deserve more protection than others but because crimes perpetrated as a result of such biases pose a danger to society that goes far beyond the individual victim.

The Supreme Court made a key ruling in 1993 upholding hate crimes statutes based on a case from Wisconsin. Critics of hate crime laws often claim that such statutes are designed solely to protect minorities, but, tellingly, Wisconsin v. Mitchell was about a white boy who was beaten up by a group of young black men and boys. Before the attack, the defendant in the case, Todd Mitchell, was heard saying, "There goes a white boy; go get him." Mr. Mitchell was convicted of aggravated battery, which ordinarily carried a maximum penalty of two years, but he was sentenced to four under Wisconsin's hate crimes law because the jury found that he had selected his victim based on race.

The Wisconsin Supreme Court eventually overturned the sentence on First Amendment grounds, ruling that it amounted to "punishing what the legislature has deemed to be offensive thought." But in a 9-0 ruling, the U.S. Supreme Court reversed that decision. In his opinion, then-Chief Justice William Rehnquist wrote that increasing or decreasing a sentence based on the assailant's motive is common in the law, and although a person's abstract beliefs may not be taken into consideration in sentencing, racial animus or other prejudice can be considered if they are relevant aggravating factors. Furthermore, Justice Rehnquist wrote, enhanced penalties are appropriate for bias-inspired conduct because it "is thought to inflict greater individual and societal harm," such as the greater possibility for retaliatory violence, emotional damage to the victim and community unrest.

In the Rosedale case, although the physical harm was done to Ms. Polis, the crime, if indeed it was motivated by the victim's sexual identity, will have done damage to all transgender people in the community who might now have reason to fear doing something so simple as going to McDonald's. Hate crimes are in a sense akin to terrorism in that their effects are far more widespread than a simple assault. And although the beating of Ms. Polis has led only to peaceful protests, that has not always been the case with hate crimes, which often breed additional violence; the riots following the beating of Rodney King are frequently cited as an example of the phenomenon.

It is important to remember that criminal prosecutions are based on the idea that the perpetrators have committed an offense against the state, not a particular person, and in the case of hate crimes, that offense is widely felt. Ms. Polis is not deserving under the law of additional protection from violence simply because she is transgender, but if Baltimore County State's Attorney Scott Shellenberger can prove that she was assaulted because of her gender identity, her assailants will deserve extra punishment.