criminal menopause
n. The stage in life during which an older, habitual criminal loses interest in crime, or when an older prisoner no longer poses any threat to society.
Examples
2003
Ted "Animal" Durbin stood over David Allen Mackey's grave and dropped a yellow wildflower onto the casket. For Durbin, the act helped provide a final good-bye to his friend. "I developed a bond with David," said Durbin, an inmate who volunteers at the hospice inside the Louisiana State Penitentiary. "This one was tough." …

Helping Mackey provided a form of redemption, Durbin said, now that he has reached "criminal menopause" — the point where people often lose interest in lives of crime.
—Brett Barrouquere, “Inmate volunteers help dying fellow prisoners at Angola's prison hospice,” The Sunday Advocate (Baton Rouge, LA), December 21, 2003
2002
As they grow more feeble and sick, geriatric prisoners also become less dangerous. At some point in life, scholars agree, a sort of "criminal menopause" sets in and felons grow less impetuous, less prone to violence. Though there are famous exceptions, national studies show that only about 2% of men paroled after 55 return to prison.
—Jenifer Warren, “The Graying of the Prisons,” Los Angeles Times, June 09, 2002
1992 (earliest)
The legislature, which opens its 1992 session March 30, needs to approve measures to allow inmates serving life sentences out on parole when they reach 45 years of age and have spent 20 years behind bars, said Secretary Richard Stalder of the Department of Public Safety and Corrections.

Attorney Keith Nordyke, who represents the interests of all state prisoners covered by a federal consent decree to reduce prison population and relieve jail overcrowding, told the committee he agreed with the secretary.

Long-term prison inmates, Nordyke said, ''tend to reach criminal menopause at 45,'' and no longer pose serious threats to law and order. ''We should move some of the older ones out of there,'' he said.
—“Louisiana prisons chief urges release of lifers at age 45,” United Press International, March 24, 1992
Notes
Thanks to three-strikes-and-you're-out laws, harsh sentences, and strict parole guidelines, the prison population in the U.S. is getting grayer by the moment. According to the Project for Older Prisoners (great acronym: POPS) and other sources, the number of inmates age 55 and over went from 6,500 in 1979 to 50,000 in 1998. Today the total is anywhere from 6 to 10 percent of American's 1.4 million-strong prison population, meaning that between 84,000 and 140,000 inmates fall into the "elderly prisoner" category. (Because they live hard lives, prisoners are generally considered to be physically 10 years older than their chronological age.) Some studies have predicted that the proportion of geriatric prisoners will increase to 30 percent of the total inmate population by the year 2025.

This has caused quite a stir in the U.S., not only because prisons are filling fast (most are already overcrowded), but because elderly prisoners cost more since they have greater health care needs. On average, it costs taxpayers $20,000 per year for a younger inmate, but about $69,000 per year for an elderly prisoner.

The irony is that as incarceration costs rise, the risks to society fall. Thanks to the widely accepted notion of criminal menopause, elderly inmates (indeed, most inmates over the age of 45) pose little or no threat to society. This is why POPS and other organizations are lobbying for legislation to enable states to parole prisoners after they reach a certain age (and so, presumably, have gone through criminal menopause).