As the sky-blue Winnebago makes its way though midday traffic in downtown Baltimore, pedestrians can't help but stare.
Onlookers giggle and pull out their camera phones. The RV, painted with the phrase "Who's Your Daddy?" offers a service most wouldn't think of using during their lunch break: DNA testing.
Demand for such tests has grown in recent decades, as a legal tool in cases of child custody and paternity cases but also as an increasingly accepted way to confirm biological ties at a time when single motherhood has skyrocketed. Some family law experts, however, worry the growing use of such tests could have unintended consequences, such as destabilizing families and hurting children.
The "mobile clinic" is operated by a New York-based DNA testing company called Health Street, whose employees travel to Baltimore about once a month to promote the service. Few choose to get tested on the spot, but the truck gets people talking, said Health Street owner Jared Rosenthal.
"It's somewhat of an in-the-closet issue," Rosenthal said of paternity tests. "We're kind of taking the covers off it — putting it on the street."
According to the latest data from AABB, formerly the American Association of Blood Banks, accredited labs performed more then 380,000 relationship DNA tests in 2010, a number that officials say is low because many more are performed at non-accredited labs. That's up from the 120,400 tests reported in 1990.
In the mid-'90s, welfare reform helped spur growth in the DNA testing industry, experts say. The federal government placed greater emphasis on encouraging women who apply for public assistance to identify the fathers of their children. More than six out of 10 women who give birth in their early 20s are unmarried, a rate that has accelerated in recent years, according to the Census Bureau.
Identifying fathers helped states track down men who had never supported their biological children, and the industry grew as labs vied to secure large state contracts, said David Bishai, a professor at the Johns Hopkins University's Bloomberg School of Public Health. But Bishai also said policymakers put too much emphasis on financial support and not necessarily better parenting.
"The dark side of this is that we have state legislation that is much more driven by money than by the well-being of children," said Bishai, who focuses on economic demography. "There's this simplistic idea that the role of the father is to supply the money in parenting and not to supply the time."
Joseph DiPrimio, executive director of Maryland's Child Support Enforcement Administration, said state and federal laws require parents seeking public assistance to seek child-support services. The availability of DNA testing can help get the child-support collection process moving more quickly and eliminate doubts, he said.
"Generally as a broad concept, the right of a child to know his or her biological parent, I think that's the important thing," DiPrimio said.
The state contracts with the Ohio-based company DNA Diagnostics Center for paternity testing. A test through the state costs about $120 for a father, mother and one child, plus a $25 application fee, said Brian Schleter, spokesman for the state Department of Human Resources.
Health Street's paternity tests cost $350, and the firm contracts with collection clinics in various states, including Maryland. The company also offers mobile drug tests, traveling to construction sites and accident scenes.
Rosenthal said people seek DNA testing for a variety of reasons that don't involve child-support conflicts — including simple peace of mind.
"There are plenty of places where people are together, and the father wants reassurance," he said.
In other cases, a person might need to prove a biological relationship to sponsor a family member emigrating to the United States or for inheritance purposes, he said. Or they have found possible long-lost siblings and want to confirm the ties.
While many on the sidewalk snicker at the sight of a mobile DNA testing clinic, some family law experts say the growing availability of such tests raises serious concerns about destabilizing families.
Jane Murphy, a family law professor at the University of Baltimore School of Law, said she's seen heart-wrenching cases where children are devastated over the results of a paternity test.
"It's not a joke to them who their father is," she said. In many cases, children had a long-term relationship with a man they believed was their father, only to find out he is not.
"There's no other father waiting in the wings," she said. "In many cases, there never will be."
Murphy believes the tests can do more harm than good in certain cases.
"Making it more available has the potential for destabilizing a lot of families where there's no biological connection between the father and the children," she said. "Biology doesn't have to define a relationship."