Prosecutors seeking more severe penalties for nine alleged gang members or associates charged in the rape of a 14-year-old girl hope to prove that the attack was part of their gang activities, an unusual and rarely successful tactic.

Mang Yang and Vang Tou Ger Vue are scheduled to appear in Ramsey County District Court on Wednesday on two counts of criminal sexual conduct and one count of crime committed for the benefit of a gang. Four of the other defendants in the November gang rape in St. Paul are juveniles; the remaining adults are expected to make court appearances later this week.

Authorities say it's not uncommon for gang members to be involved in sexual assaults, but victims are often reluctant to come forward. Even when they do, it's difficult to prove that the crime is "committed for the benefit of a gang," a felony offense that carries a maximum sentence of 40 years in prison.

In the past 14 years, gang members charged with committing a crime for the benefit of a gang in addition to the original sexual assault offense have been convicted on both charges in just 31 percent of the cases.

"It's a tough charge to get," Maplewood Deputy Police Chief Dave Kvam said. "I'm certain we have sexual assaults that are perpetuated by gang members, but whether their crime had anything to do with their affiliation to a gang, I can't point to that."

Being a gang member and committing a sex crime is not enough to convict on the gang charge, authorities said.

"It's pretty tough to quantify that one necessarily leads to the other in a direct, causational way," he said. "You have people associated with gangs, it just stands to reason that they're involved in crime, including sexual assaults."

Data from the State Court Administrator's Office show that since 1998, there have been 76 cases, including the November attack, in which defendants were charged with both criminal sexual conduct and a crime for the benefit of a gang. There were convictions on both counts in just 21 of those cases, most recently in two 2005 cases.

Not done since 2009

The last time prosecutors linked a sex assault to the gang crime charge was in 2009 and involved four juveniles with alleged ties to an upstart gang known as Mafia Gangster, or MG.

The four were accused of taking a 13-year-old Minneapolis girl by bus to a residence in St. Paul, where they repeatedly raped her, according to a statement released at the time by the Ramsey County attorney's office.

None of them was convicted of the gang charge. Records are available for only one defendant, a male who was 16 years old at the time. He pleaded guilty to first-degree criminal sexual conduct in the 2009 attack and to third-degree criminal sexual conduct in a 2008 rape of the same girl. The gang charge was dismissed as part of a plea deal.

In the current case, Yang, Vue and the seven other defendants also each face a kidnapping charge.

According to allegation in court documents:

The defendants plied the victim with alcohol at a party in November, forcibly dragged her into a vacant house in the 200 block of White Bear Avenue in St. Paul, held her down and sexually assaulted her.

The suspects are allegedly members of, or have ties to, the True Blood (TB22) street gang. The gang originated in St. Paul and has about 40 members.

St. Paul police have said the incident was not an initiation for the defendants, or a "sex in" for the victim, which is when a girl is initiated into the female counterpart of a male gang.

Staff writer Anthony Lonetree contributed to this report. Chao Xiong • 612-270-4708 Twitter: @ChaoStrib