Nisbet, 31, of Livermore was charged Dec. 7 with 65 felony counts for allegedly sexually abusing two boys whom he'd taught.
Court documents say Nisbet committed hundreds of individual acts against each of the boys, and that they both "provided a detailed statement" that "clearly described the type of sexual abuse."
Nisbet also talked to one of his victims on the phone, court documents stated, in which he admitted to making a "mistake" and apologized for what he'd done to the two boys.
At the time of his arrest, Nisbet had an estimated 175 boys from across the Tri-Valley enrolled in the GRIP Junior Golf Academy he created at the Las Positas Golf Course. Hundreds of other boys ages 12 to 17 have been through Nisbet's academy since he was recruited in 2006, and thousands had been through the GRIP academy he originally founded in Michigan in 2002. Livermore police have said they think Nisbet may have abused boys there, as well as possibly in North Carolina, Mississippi and Alabama.
Nisbet was well known and well liked, had a reputation for winning and was successful at getting scholarships for young golfers. His youth team won the PGA Junior League Championship in 2012.
Worried about the extent of the possible abuse, the father of one of the boys coached by Nisbet approached Kelly Dulka, executive director of the East Bay YMCA who is also a therapist and an expert in child sexual abuse. She and colleague Tonya Richardson, also an expert and a curriculum developer of safe environments for children, held two forums recently at the Y in Dublin to offer information to parents.
"Moms who had kids who were coached by (Nisbet) were calling for information," Dulka said.
Their advice to parents: Watch your children, be patient, talk to them and listen.
"I think it's really important to have a frank conversation with kids when an issue comes up around someone they know," Dulka said.
While few victims ever step forward to acknowledge they were sexually abused, she said, "The symptoms are going to come out."
"The advice I'd give to parents is just listen," Dulka said. "Giving a message that you're ashamed or embarrassed about this may cut them off. Sometimes it takes months to get a disclosure. ... Maybe they'll talk about it happening to a 'friend.' Finally they'll acknowledge that they're a victim."
The number of those abused may be hard to pin down, Dulka said.
"It's a crime that is very hard to quantify because of the number of people that never disclose it," she said.
The best guess by researchers, Dulka said, is that one in three girls and one in six or seven boys are victims of sexual abuse by the age of 18. She said often victims do not acknowledge their abuse until they are 30 or 40 years old.
"In a case like this, it might be years before victims come forward," Dulka said.
In addition to talking to their children, parents need to be aware of changes in behavior, Richardson said.
"It could be destructive, it could be they're acting very low-energy, always sleeping, showing signs of depression. All of a sudden they don't want to take baths or showers or they're taking more frequent baths or showers," she said. "For kids in middle school, sometimes they may not want to be undressing in a locker room situation. They might become uncomfortable."
Richardson said those changes could also include a sudden loss of interest in an activity that used to interest them.
Other changes could include an inability to control anger or making excuses not to be around their abuser, Dulka said, or "precocious knowledge of sex or more interest in it."
"Getting overstimulated around sexual issues could be a red flag," she said.
The issue poses a unique problem because some of the families involved in the golf program come from cultures that may hesitate to discuss issues they perceive as shameful and an "it can't happen here" mentality in the area, Dulka and Richardson said.
Dulka said worries about "stranger danger" are small compared to the numbers of those abused by someone they know.
"An estimated 95% of abuse occurs by someone fairly well known to the child, either related to the child or in close proximity: family members, friends, neighbors, coaches, people that the kids and the families trust," Dulka said. "In the case of the golf coach, families said they were shocked, that they would trust him with their own lives, they were that close to him."
Richardson said typically, sexual predators begin by getting to know the entire family.
"The beginning of the grooming process starts out very innocent, engaging in everyday activities," she added. "Predators will see where they can go, hanging out, giving gifts. It can be a slow process where they are ingratiating themselves in the family. It's pretty common for the adult to prefer relationships with kids and kind of shy away from adult relationships."
Often, a child will describe himself and his abuser as "best friends."
"That makes it really hard for the child to disclose," Dulka said, "because they feel that they are betraying the perpetrator that they've learned to love and care for and they're not going to be believed because the parents care for the perpetrator."
Nisbet's felony charges include both sexual assault and sexual abuse. Sexual assault is a physical act, while sexual abuse includes acts such as exposing an underage person to pornography. Charges against Nisbet included oral copulation by force, oral copulation of a person under the age of 16, oral copulation of a person under age 18, lewd and lascivious acts with a child age 14 or 15 years, distribution or exhibition of lewd material to a minor, and arranging a meeting with a minor for the purpose of engaging in lewd and lascivious behavior.
Nisbert was recruited in 2006 after working as golf pro at a Birmingham, Ala., country club and at Beech Woods Golf Course in Southfield, Mich., where a website said he'd coached 3,500 young golfers.
His arrest came a day after the PGA's Northern California Section announced that it gave him its 2013 Junior Golf Leader Award "for his dedication and leadership in developing a wealth of exciting and educational golf programs for juniors."
In its news release about the award, the PGA quoted Nisbet as saying, "Junior Golf is something that I am extremely passionate about."
Nisbet has been permanently expelled by the PGA of America and has been fired from the golf course in Livermore where he held the GRIP Academy. He remains held without bond in Santa Rita Jail and is set to enter a plea on Jan. 14.
A second set of forums, focused on preventing sexual abuse, is set for later this month, although the dates have not yet been finalized.