The every-other-weekend dad, born from two generations of soaring divorce rates, was once a conventional part of American culture. In recent years, more couples have been agreeing to parent after divorce as they did in marriage: collaboratively.
Now lawmakers are accelerating this trend toward co-parenting, with legislatures in more than 20 states this year considering bills that would encourage shared parenting or make it a legal presumption — even when parents disagree.
Kentucky this year passed a law to make joint physical custody and equal parenting time standard for temporary orders while a divorce is being finalized. Florida's legislature overwhelmingly approved a bill last year to presume equal time for child custody plans, but it was vetoed by the governor. And in Michigan, lawmakers are considering a bill that would make equal parenting time the starting point for custody decisions.
The legal push for custody arrangements follows years of lobbying by fathers' rights advocates who say men feel alienated from their children and overburdened by child-support obligations. This movement is gaining new traction with support from across the political spectrum, as more lawmakers respond to this appeal for gender equality and, among some conservatives, the frustration of a newly emboldened constituency of men who say they are being shortchanged.
Many of the legislative gains recently have been propelled by the National Parents Organization, a group with roots in the fathers' rights movement but now a broadened focus on children's rights and parental equality. The organization includes some women members.
Critics of the bills, including women's rights groups and some legal associations, say that stricter laws will roll back important protections against abusive or controlling former spouses and take discretion away from judges who are tasked with deciding what is in the best interest of children. They also say that the bills, which would directly apply to only the 10 percent or so of divorcing parents who cannot come to an agreement, are unnecessary because more divorcing parents are already choosing shared custody.
Laws that require joint physical custody could also lead to the elimination of child support in some states, women's advocates say, disrupting a system that was designed to help women, who have historically been paid less in the workforce while performing more unpaid labor at home.
"That disparity in assets and earning power doesn't simply disappear at separation," said Molly Dragiewicz, an associate professor at Queensland University of Technology in Australia who wrote a book about domestic abuse and divorce.
Proponents emphasize that the bills overwhelmingly address parents who are otherwise fit and not abusive. They say that family courts are out of step with modern families and that the current system benefits highly paid lawyers while depriving millions of children of the chance to build meaningful relationships with their fathers.
"The way the system is set up now, two parents enter the courtroom. When they leave, one is a parent, and the other is a visitor," said Christian Paasch, 37, chair of the National Parents Organization of Virginia.
A presumption of shared parenting would replace the "winner takes all" approach currently embedded in the law, he said, and replace it with a new message: "You will both still be parents, and you both matter to your children."
For more than a century, court decisions were guided by the "tender years doctrine," a vestige, legal scholars say, of the cult of domesticity that put women on a pedestal as instinctive caregivers.
That began to change in the 1960s and 1970s, as more women joined the workforce and as no-fault divorce laws ushered in a wave of divorces.
The guiding principle in custody rulings changed to a more flexible and gender-neutral "best interest of the child" standard, and states overturned previous rules that disallowed joint custody.
But despite changing laws, judges continued to use their discretion to award primary physical custody overwhelmingly to mothers in many places, reflecting a lingering bias, many say.
Fathers' rights groups and other advocates have worked to make the laws stronger.
Statutes in the District of Columbia include a presumption that joint custody is in the best interest of a child, except in cases of abuse or neglect.
In Maryland, advocates have promoted bills that would create a presumption of joint legal decision-making and equal parenting time, but they have not made it out of committee.
In Virginia, Sen. Barbara A. Favola (D-Arlington) is introducing a bill that would require judges to communicate in writing the rationale for their custody decisions.
This "baby step" might open the door to more joint custody decisions, she said, because a written ruling could give parents something to use for appeals and provide a chance to evaluate whether bias is influencing decisions. Favola said she sees both sides of the issue: She wants to make a statement that children benefit from having two involved parents, she said, but she also believes that the existing "best interest" legal standard makes sense, since joint custody is considered best practice unless there are mitigating circumstances.
Paasch, who has been advocating for a stronger shared-parenting law in Virginia, said he believes that judicial bias played a role in his custody case. When the Air Force veteran and federal employee was separated a decade ago, he was afraid he would lose a connection to his son, then a year old.
He and his son's mother could not agree on a custody arrangement, so they went to court, where Paasch asked for primary custody. A court-appointed investigator tasked with representing the interests of his child recommended equally shared custody.
A judge in southern Virginia instead gave primary custody to the mother and granted Paasch visitation, he said.
He appealed and in a settlement worked out an agreement to have physical custody for almost half the time.
Today, he talks with his son almost every day and has physical custody about 30 percent of the time, when his son has breaks from school. The son now lives out of state with his mother the rest of the time.
Maintaining close contact and being involved in important decisions has required frequent court intervention. If the laws had given fathers more explicit rights, he believes, the process would have been less contentious.
"It took us eight years and eight or nine times in court and about 15 attorneys to get to this point," said Paasch, who has since married and whose wife, Kristen, has become involved in advocacy for shared parenting.
Extensive social-science research shows that children benefit from having an involved father. Children with active fathers tend to have higher self-esteem and better academic records.
A meta-analysis of research on the effects of shared parenting on children in 15 countries also showed benefits across a range of emotional, behavioral and physical health measures.
"The custody laws in our country were based on the sexist belief that mothers are better than fathers at raising children," said Linda Nielsen, a professor of adolescent and educational psychology at Wake Forest University. " . . . Well, the research does not support that."
Advocates for shared parenting frequently cite a broader set of statistics showing worse outcomes, such as a greater risk of incarceration or dropping out of high school, for children raised in any single-parent households, including those in which parents never married, a category that represents 40 percent of all U.S. births today.
This can be misleading, some academics say, because never-married parents are far more likely to be very poor, which by itself can lead to negative outcomes for children.
Some researchers question what conclusions can be drawn from studies that show benefits from shared parenting, since children being raised in joint custody arrangements probably have parents who get along better — a situation that would not necessarily extend to those compelled to adopt shared custody.
"It's not the amount of parenting time but the quality of parenting and the quality of co-parenting that matter," said Robert Emery, a professor of psychology at the University of Virginia and the author of "Two Homes, One Childhood."
"Kids don't count the minutes and the percents, but they sure respond if they have a good relationship with their mom and dad or if they are caught in the middle of a war zone."
Rather than giving courts the power to make these changes, Emery and others recommend alternative resolution strategies.
Many states are promoting mediation and the creation of parenting plans in lieu of custody litigation. Such plans spell out in minute detail how each parent will take responsibility for the care of each child. Studies show that this process usually leads to a more equitable division of parenting time.
Many states, including Virginia, have also changed the vocabulary of child custody to promote a less adversarial outcome, with "decision-making" and "parenting time" replacing "legal custody" and "physical custody."
But for many fathers, a gradual approach to change is unsatisfying if they are separated from their children now.
Many become politically involved through local divorce-support groups, where they go to receive legal counsel, vent frustrations and get support from other men, although some of these fathers' groups have drawn heavy criticism for promoting the notion that false claims of domestic abuse are widespread.
A growing number of stay-at-home dads and younger dads are also pushing for family court changes because they are committed to caregiving and want to redefine gender roles.
Shared parenting can be a boon to women, they say, giving them a chance to return to school or invest in work or new relationships, just as it can help men break out of their previous roles.
"If we are going to create a new generation of men who view caregiving and work at home as meaningful work, we have to be willing to let them into spaces we traditionally don't let them into and create protections for them in the event that their marriages don't last," said Mark Greene, a divorced father and writer who has shared custody of his son.
CORRECTION: An earlier version of this story misidentified the mother of activist Christian Paasch's son as his ex-wife. It also suggested that the National Parents Organization is solely a fathers' rights group. This version has been corrected.