Mixed messages came out of a hearing in Detroit federal court Tuesday on the safety of Flint water.

Is Flint water now safe? U.S. District Judge David M. Lawson wanted to know.

"I can unequivocally state the drinking water in Flint is safe, as defined by the (Envirnmental Protection Agency's) Copper and Lead Rule," said Attorney Richard S. Kuhl, an assistant attorney general who is representing the state.

Lawson called Kuhl's addendum, "as defined by the Copper and Lead rule," an "interesting dodge."

Kuhl then restated: "Unfiltered tap water that came from the Flint water supply is safe to drink," but added that no matter where your water comes from, or how well it's treated, there is still "some risk of contamination."

According to the Michigan Department of Environmental Quality, lead in the Flint water supply has dropped below the "action level" of 15 parts per billion.

If the water is now safe, why then, haven't officials told residents they can stop using filters? asked plaintiff attorney Dimple Chaudhary of the Natural Resources Defense Council.

"We are still concerned about the lead service line removals and how that will impact the system," the attorney said when asked the question by Lawson. "We are still recommending residents don't drink unfiltered water."

Kuhl said it's a "political decision" and not a "water compliance decision."

Kuhl said residents should continue to only drink filtered water out an "abundance of caution," and because while the lead delivery lines are being replaced -- an effort that could take three years -- there is a chance backwash could cause lead levels to spike.

And "we realize there has been a loss of trust in the city," he said.

The judge asked Kuhl if he had personally consumed Flint water since it's become "safe." The attorney said he hadn't visited Flint in months.

"The force of your argument might be enhanced if you actually did take a trip," Lawson responded.

Kuhl said he plans to take a trip to Flint sometime soon with his wife and son to visit a Titanic artifacts exhibit at the Sloan Museum. He'd drink the water at that time.

Lawson later joked they could create the "Kuhl Rule" to determine the water safety.

The purpose of the hearing was to argue whether Lawson should grant a defense motion to lift a November injunction requiring the state and city of Flint to verify residents' faucet water filters are properly installed, and to deliver bottled water to those homes where that can't be verified.

State officials claim they're using an optimal water delivery system, complying with EPA and MDEQ guidelines and now have lead level testing equal to or below levels in thousands of other water systems across the nation.

The plaintiffs in the case, who include the National Resources Defense Council, American Civil Liberties Union, Concerned Pastors for Social Action and others, filed a second motion claiming the state hadn't lived up to the requirements established in by Lawson, and the judge appeared to agree, although he took both motions under advisement.

Lawson accused the state of "slow-walking" progress toward compliance with the order he issued 2 1/2 months ago and said he was "unimpressed" by the efforts.

Assistant Attorney General Michael F. Murphy was peppered with questions about how the door-to-door effort ensures all homes have been inspected for filters.

He said there are currently 87 employees of with the Community Outreach Resident Education (CORE) Program, the entity doing the work, and nearly 34 still in training.

Lawson seemed annoyed it took officials nearly two weeks after his initial order to post job openings. The goal is to hire a total of 180 employees, Kuhl said.

Murphy said CORE employees had visited 39,000 homes in about five months, but must return to 28,000 residences where residents weren't available, or where crews were otherwise unable to inspect.

Murphy told Lawson the workers would ask residents if they had filters, but weren't necessarily insisting on inspections in cases where they were already installed.

"Do you not think that flies in the face of my order?" Lawson asked. "If you don't make an effort, then you haven't complied with the order."

Kuhl then stepped up to the podium and whispered something into Murphy's ear. Murphy then amended what he'd previously said and claimed workers are insisting on performing inspections, even if residents say they already have filters properly installed.

For residents who do not have filters, Lawson ordered officials to start a bottled delivery service.

"They are gathering data," Murphy said. "Right now, there is no organized plan of delivery for delivery of bottled water."

Defense attorneys said the "sophisticated" and "massive logistical" effort required to deliver bottled water within the judge's order was "hopelessly unlike anything the city has ever done."

Attorneys for both sides are currently in mediation. Chaudhary said there are plans for mediation sessions this coming Friday and Saturday.

In the meantime, Lawson demanded a more specific plan of compliance be produced by next week.

He asked for benchmarks on hiring targets, daily home-visit quotas, bottle delivery options, possible vendors and cost, "typical things that one would expect."