Gov. Deval Patrick finally broke a week of silence yesterday and said he fired the head of the state’s Sex Offender Registry Board and put its executive director on leave in part because they tried to pressure a hearing officer to list the governor’s brother-in-law as a sex offender.

Patrick said the move to list Bernard Sigh — who was convicted of raping the governor’s sister — as a sex offender “involved some inappropriate at least, maybe unlawful pressuring by the chair and the executive director of a hearing officer to change an outcome of a case.”

In discussing the reasons he terminated Saundra Edwards, the registry board chairwoman, however, Patrick also revealed for the first time a 2008 whistle-blower lawsuit by the hearing officer who ruled that Sigh should not be listed as a sex offender.

The Herald first broke the story that Sigh had failed to register as a sex offender in Massachusetts in 2006, during Patrick’s first campaign for governor. Sigh was convicted in 1993 of raping his wife, served four months in jail and was put on five years’ probation.

“It turns out that case is the case that arose out of my brother-in-law’s experience way back at the beginning of the first campaign when the Republican Party, sorry to say aided by the Herald, nearly destroyed their lives,” Patrick told reporters yesterday.

The governor’s remarks capped a week in which the Corner Office had remained mum about Edwards’ sudden ouster. Patrick — who was on a trade mission in Europe last week — also put the registry’s executive director, Jeanne L. Holmes, on leave.

Patrick’s office had for days declined to detail why the governor made the changes until releasing a statement Friday saying he had “lost confidence” in the pair.

“Not every execution needs to be in public,” Patrick said yesterday.

The hearing officer in Sigh’s case, identified as A.J. Paglia, determined in August 2007 that Sigh did not have to register as a sex offender for his California conviction. But Edwards, Holmes and others tried to change his decision, according to Paglia’s lawsuit and his attorney John Swomley.

It’s unclear why Sigh was taken off the sex offender registry. Sex offender hearings are shrouded in secrecy and decisions are subjectively based on criteria such as age at the time of the crime and whether the offender has a home.

Paglia, who now serves as chief of staff for Senate Minority Leader Bruce Tarr, alleged that after he declared Sigh no longer dangerous, he was demoted and ordered to go to retraining before he eventually resigned and filed the whistle-blower suit in December 2008.

The registry settled with Paglia in February for $60,000, the governor’s office said.

Patrick yesterday cited an “accumulated loss of confidence” in Edwards and Holmes, including a series of board decisions that have been since reversed by the Supreme Judicial Court; reports that they had created a hostile work environment; and criticisms that they dragged their feet on updating the board’s regulations.

Patrick said his administration had started a “months-long” process of evaluating the registry board, and “the folks who were setting the tone over there, the chair in particular, have been changed out.”

Patrick’s involvement in Sigh’s case raised some eyebrows yesterday.

“Our laws are our laws — whether they’re for Deval Patrick’s family or everyone else,” said victims advocate Laurie Myers. “The fact is his brother-in-law committed a horrendous crime against his wife, so why is he trying to blame two women who were trying to do their jobs? I want them to scrutinize every single classification.”