Individual A contended that for many years he suffered several panic attacks that led to “periods of unemployment, career changes, bouts of depression, hospitalisation and long-term psychiatric treatment.”

But Individual A never connected those problems to Hastert’s abuse until 2008 when he learned for the first time that the former coach had also molested someone else decades ago, according to the suit.

Hastert’s attorneys said Monday they have no comment on the lawsuit.

Hastert, 74, faces anywhere from probation up to five years in prison when he is sentenced Wednesday, although his plea agreement with prosecutors calls for a sentence of no more than six months behind bars.

He pleaded guilty in October to one count of illegally structuring bank withdrawals to avoid reporting requirements, admitting in a plea agreement that he’d paid US$1.7 million in cash to Individual A to cover up unspecified misconduct from decades earlier.

Individual A has never been publicly identified and is not expected to testify at Hastert’s sentencing hearing. He filed the suit Monday under the name James Doe, saying the use of his real name would cause “great psychological damage to him in the form of shame and embarrassment.”

When reporters approached the middle-age husband and father in February, Individual A said he didn’t want to be rude but was “not interested” in speaking publicly and walked away. His wife acknowledged that her husband was a “victim”.

In a court filing earlier this month, prosecutors alleged Hastert sexually abused five students when he was a teacher and wrestling coach at Yorkville High School. The abuse allegedly occurred in hotel rooms during team trips and in empty locker rooms, often after Hastert coaxed the teens into a compromising position by offering to massage them.

Prosecutors alleged that Hastert performed a sex act on two wrestlers at separate times and inappropriately touched two other wrestlers once each while giving them massages. The filing also alleged that Hastert set up a La-Z-Boy-type chair outside the locker room showers in order to sit and watch the boys.

Shortly after Hastert was approached by the FBI about numerous high-dollar bank cash withdrawals, he told authorities he was being extorted by Individual A, who had made false claims of sexual abuse against him, prosecutors said. In March 2015, Hastert recorded two calls with Individual A, but investigators noted that Individual A’s tone and comments did not sound like an extortionist.

The lawsuit filed Monday said Hastert was “a trusted friend” of Individual A’s family. In 2008, after he was “made aware” for the first time that Hastert had abused someone else, Individual A met with Hastert to “confront him about what he had done,” the suit alleged.

After acknowledging “the lifelong pain and suffering he caused,” the suit alleged Hastert asked Individual A how much he thought it would take to compensate him. Individual A suggested US$3.5 million, which Hastert agreed to. In exchange, Individual A agreed not to sue for personal injuries or “seek any public acknowledgment of the misconduct,” the suit said.

According to prosecutors, when FBI agents confronted Individual A last year, he told them Hastert had him stay in a motel room overnight with him while returning from a wrestling camp in the 1970s when he was 14. Individual A had complained about a groin pull, so Hastert said he wanted to check it out and began massaging his groin area after telling him to remove his underwear, prosecutors said.

When it became clear that Hastert was touching him in an inappropriate way, Individual A jumped off the bed, but he said he was confused and embarrassed and apologised to Hastert. He told authorities Hastert massaged his back and the two slept on the same bed.

While Individual A is not expected to attend Wednesday’s sentencing, prosecutors have confirmed that Individual D, who told authorities that Hastert performed a sexual act on him in the school locker room when he was 17, will testify under oath.