Child custody law and related judicial determinations have historically been underscored in the United States by this one centrally perceived truism, as expressed by a family law researcher and sociology processor: "Unless the mother was dead or in jail or mentally ill, the father wouldn't get the child."

Although mothers still predominate as heads of households with single parents and children, the long-term pattern of single fathers virtually never having primary custody is changing somewhat and reinforced by statistics that evidence a clearly evolving trend.

For example, a single dad living with the kids as head of the household was both puzzling and flatly aberrational in the United States in 1950. At that time, the number of such households stood at just 1.1 percent of the total. The figure jumped to 6-plus percent in 2000 and now resides at about eight percent.

Moreover, there has been about a 27 percent increase in families led by single dads just within the past decade.

Why the strong uptick? Family law experts and demographers say that much of the change owes to changed ideas concerning child rearing, with greater acceptance of shared custody and more unmarried couples.

Key, too, is that the American workplace looks far different now than it did in 1950. Then, relatively few women ventured outside the home to work. Now, the norm has flipped and also encompasses many stay-at-home fathers.

Despite the shift, the change should not be overstated, since a clear majority of single parents are still mothers (7.2 percent of households versus 2.4 percent led by single fathers).

Even so, the difference from earlier times, even if far from seismic, is definitely noticeable to people who are paying attention.

"There is a visible presence now of single men caring for their kids," says a public policy professor at Johns Hopkins University. "We didn't see that a few decades ago."

Related Resource: Bloomberg, "Single-Dad Courtroom Wins Show Greater Embrace of New Families" July 24, 2011