Not a single welfare recipient or applicant has tested positive for banned drugs in a Michigan pilot program, part of the growing practice of screening beneficiaries of government assistance for drug abuse.

The program, which ends on 30 September, may face renewed scrutiny in the wake of Wisconsin congresswoman Gwen Moore’s proposed legislation to force taxpayers with more than $150,000 of itemized deductions to submit to the IRS a clear drug test. Under the legislation, applicants who refuse the test would be required to take the significantly lower standard deduction when filing their taxes.

Moore’s office said drug-testing welfare recipients and applicants is “blatantly unacceptable” and pushes a stereotype that impoverished individuals are more susceptible to substance abuse than other, wealthier individuals who are beneficiaries of government programs.

“Congresswoman Moore finds it shameful that states like Michigan, Wisconsin and Florida continue to push these discriminatory policies under the guise of fiscal responsibility,” Moore’s communications director, Eric Harris, told the Guardian.

“Drug-testing struggling families and individuals as a condition of eligibility for vital, life-saving social services is blatantly unacceptable and the insinuation that those battling poverty are somehow more susceptible to substance abuse is as absurd as it is offensive.”

The Michigan program began last October and covers Allegan, Clinton and Marquette counties. As of May, a total of 303 applicants and recipients for the state’s Family Independence Program, which provides temporary cash assistance, have participated in the pilot program. Zero have tested positive, the state said. When the program concludes, the state department of health and human services has 60 days to produce a report on its results.

Michigan’s governor, Rick Snyder, who signed legislation in December 2014 to launch the pilot program, declined to comment on the results so far.

“The governor will wait until the pilot program has concluded and the report is delivered, as required by the legislation, to reach any conclusions,” said Snyder’s spokeswoman, Anna Heaton.

Several states with similar programs have produced similar results. In Tennessee, for example, only 65 of nearly 40,000 applicants for a cash assistance program tested positive for drugs. A program in Missouri had just 48 positive tests out of nearly 39,000, according to ThinkProgress – a total of 0.001%. Missouri officials told the news outlet the program will probably cost $1.35m over its initial three-year period.

Mississippi, whose program is similar to Michigan’s ongoing pilot, netted two positive results out of 3,656 during its first five months, costing the state roughly $5,000.

Michigan’s state legislature appropriated $300,000 for the pilot program, although a health department spokesman, Bob Wheaton, said the state has spent only $300.

Under the Michigan law, if a 50-question screening prompts state health officials to suspect an applicant uses a controlled substance, the individual must submit to a substance abuse test. If the applicant refuses, they would be ineligible to receive benefits for six months. No one in the pilot program refused, Wheaton said.

If anyone tests positive for an illicit drug, the state will refer them to treatment, Wheaton said, “and they will continue to receive benefits as long as they’re willing to undergo treatment”. If a person tests positive twice, he continued, they will have cash assistance terminated until submitting a negative drug test.

Michigan has a history of drug testing welfare recipients. In 1999, the state implemented a pilot program to randomly test welfare recipients across the state. It ended after five weeks when a judge found the program to be unconstitutional.

Only 21 of the 268 individuals subjected to a test under the randomized pilot program yielded positive results for drugs – about 8% – with all but three for marijuana.

The results of the current program shouldn’t come as a surprise, said Rana Elmir of the American Civil Liberties Union of Michigan, which successfully challenged the 1999 program in court and called on the state to abandon the current iteration.

In 2003, the ACLU reached a settlement with the state, allowing it to conduct drug tests only when there were reasonable suspicion of drug use, Elmir said, similar to what’s used presently.

“This program was voluntarily scrapped by the state because it proved to be unproductive and expensive,” Elmir, the deputy director of the Michigan ACLU chapter, said in an email.

“It is foolish for the state to the same thing today, yet expect different results,” she continued. “We call on DHHS to end this ineffective program immediately. Not only are they humiliating and potentially unconstitutional, such programs are clearly a flagrant waste of resources that reinforce stereotypes about poor people.”

Individuals on public assistance are not more likely to use drugs than others, Elmir said. Indeed, the nonpartisan Senate Fiscal Agency noted in its analysis of the Michigan program at the time it was passed: “The percentage of welfare recipients who use illegal drugs is similar to – and only slightly higher than – the percentage of drug users among the rest of the general population.”

Elmir said resources should be invested to train government employees to “appropriately screen and identify those with addictions and help them through expanded treatment plans”.

“Not only has this worked in other states,” she said, “but addiction experts agree that this is the best tactic to help those dealing with addiction.”

Harris, of congresswoman Moore’s office, said drug and substance abuse “knows no economic or social distinctions”.

“As we’ve seen time and time again,” he said, “these misguided policies are devoid of any scientific credibility and have proven to be a colossal waste of our time and money.”