Editor’s Note: Danny Cevallos is a CNN legal analyst and a personal injury and criminal defense attorney practicing in Pennsylvania and the U.S. Virgin Islands. Follow him on Twitter @CevallosLaw. The opinions expressed in this commentary are solely his. This commentary contains sexually explicit references.

Story highlights

Danny Cevallos: Bill Cosby charged with aggravated indecent assault. Prosecution's main evidence testimonial -- including Cosby's own

It's possible that testimony about other alleged incidents may be admissible. If found guilty, maximum sentence could be 10 years

CNN  — 

On Wednesday, Bill Cosby was charged for the first time with crimes of sexual violence in the Commonwealth of Pennsylvania. The magisterial district justice set bail at $1 million and ordered him to surrender his passport. Cosby has denied the allegations against him, and his defense team is now preparing for the preliminary hearing.

What exactly do the charges mean? What are his possible defenses? And if the commonwealth can actually prove this case beyond a reasonable doubt, what could happen to Cosby?

The charges

Cosby is charged with aggravated indecent assault. Crimes of sexual violence come in many varieties, and modern criminal codes have evolved to cover a spectrum of offenses. For example, in Pennsylvania, some of these include rape, involuntary deviate sexual intercourse, sexual assault, indecent assault and aggravated indecent assault. Each of these crimes is similar but distinct from the other.

The evidence

Aggravated indecent assault is not a crime requiring actual intercourse; it only requires minimal penetration of the genitals or anus of a complainant by any part of the defendant’s body, including a finger. The commonwealth must prove additional facts, such as that penetration happened while the complainant was unconscious; that the defendant substantially impaired the complainant using intoxicants; or simply that there was no consent.

Some sexual violence cases involve rape kits and other scientific evidence. This is not one of those cases. The prosecution’s case depends almost entirely on testimonial evidence. That, by itself, is not an obstacle to prosecution; the uncorroborated testimony of a sex offense victim may be sufficient to establish the guilt of the accused.

Here, the prosecution is relying not only on the testimony of the victim, but apparently the testimony of her mother, and, more recently, whatever statements Cosby has made or may make on the witness stand if he chooses to testify.

What about his other accusers? Can they testify?

As with many things in the law, the answer is it depends. This will be one of the major pretrial battlegrounds in the Cosby prosecution, so it’s worth discussing early on. The general rule is that evidence of other crimes, wrongs or bad acts cannot be used to show that on a particular occasion the person acted in accordance with some alleged bad character.

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However, that same inadmissible evidence may be admissible for another purpose, such as establishing motive; the identity of the perpetrator; or a common scheme, plan or design of crimes if they are sufficiently similar.

This is one of those situations where criminal defense attorneys complain that the exceptions swallow the protections of the rule.

So, for example, testimony from other women about alleged prior attacks is presumptively not allowed, but an accuser may be permitted to testify if there is significant factual similarity, such as a grooming method or a particular use of specific drugs.

The bottom line is this: Even if the defense successfully keeps out the majority of other accusers’ evidence and if Pennsylvania prosecutors successfully introduce only a fraction of these alleged “other acts,” the effect could still be devastating to this defendant.

Even a single other similar act could prejudice the jury against this defendant. That’s why this evidence should be admitted only if legally appropriate and why defense attorneys complain it is often admitted too liberally.

Some defenses

Where a case relies heavily on the credibility of the complainant, the defense must attack the credibility of the complainant. The credibility of a victim of sexual violence is measured according to the same standard applied to any other crime victim.

Of course, there are some special rules in cases of sexual violence.

The Rape Shield Law generally bars certain evidence about a complainant’s past sexual conduct. The purpose of the rape shield law is to preclude a defendant from shifting the focus of the trial from the defendant’s culpability to the victim’s virtue and chastity. However, there are exceptions to this rule, too.

For example, evidence of a victim’s past sexual conduct with the defendant may be admissible if consent is an issue in the case.

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There’s also the issue of preindictment delay. Even where a case is brought within the statute of limitations, the due process clause may still require dismissal of a criminal case if the delay in charging caused substantial prejudice to the defendant’s right to a fair trial and that the delay was used intentionally to gain tactical advantage over the accused.

The longer a prosecutor waits to charge a defendant, the harder it is for the defendant to prepare a defense. In fairness, the prosecution’s case might weaken during that time, if, say, a material witness dies or vanishes. But on the whole, when the prosecution waits until the end of the statute of limitations to charge, the defense suffers a disadvantage.

The Supreme Court has said that in some cases, it may be too difficult and the case should be dismissed. It’s rare to get a case tossed on these grounds, but it’s something to consider in this case.

Cosby’s potential exposure

What is this defendant looking at in terms of potential punishment?

Aggravated indecent assault is a second-degree felony, which has a statutory maximum of 10 years’ incarceration. Of course, the maximum does not always reflect an actual, expected sentence. It’s just a maximum. That’s why Pennsylvania, like other states and the federal system, requires courts to consider the relevant adopted sentencing guidelines.

PHILOADELPHIA - DECEMBER 12:  at Temple University's Liacouras Center for the world premiere of "Fat Albert" December 12, 2004 in Philadelphia, Pennsylvania. 
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As a general rule, sentencing guidelines enumerate aggravating and mitigating circumstances; assign scores based on a combination of first a defendant’s criminal record (“prior record score” or “PRS”) and secondly on the seriousness of the crime (“offense gravity score” or “OGS”); and then use this formula to suggest a range of punishment for each crime. There’s actually a matrix consulted by Pennsylvania lawyers in calculating guidelines; just plug in the defendant’s numbers and it spits out a range.

A defendant such as Cosby would likely be what is known as a “zero” in terms of his “prior record score.” While being a zero is usually a derogatory term in regular life, in the world of sentencing, you always, always want to be a zero. It means you have no significant prior record, which is a huge factor in calculating sentences.

While Cosby’s prior record score is low, “F2” (second-degree felony) aggravated indecent assault has a high offense gravity score. If convicted, Cosby’s “guidelines sentence” would likely be between 22-36 months’ incarceration.

But even these formulae are not binding. Despite the recommendations of the sentencing guidelines, trial courts can and do sentence defendants above the guidelines’ recommended sentence.

The only line that a sentence may not cross is the statutory maximum sentence – and here, that’s 10 years.

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