IN ITS latest report on minority voting rights in America, published this month, the bipartisan United States Commission on Civil Rights reports that a range of restrictive voting measures have been enacted by states in recent years. They range from laws demanding that voters produce specific forms of identification to reductions in the number of locations where people can cast their ballot. These laws have a disproportionate effect on the ability of minority groups to exercise their voting rights. And thanks to a 2013 Supreme Court decision that weakens federal authority to restrict such laws, they are remaining on the books.

The 1965 Voting Rights Act and its extensions helped dismantle generations of rules and regulations that had disenfranchised minority voters—and in particular black Americans. One of the act’s major provisions mandated that jurisdictions with a history of voter rights discrimination, including Texas, North Carolina, and seven other states, had to “pre-clear” new voting requirements. This involved persuading the federal government or a three-judge panel that the requirements would not be discriminatory in impact.

But in 2013, the Supreme Court struck down the pre-clearance process. The majority opinion suggested that the act had worked, and that it was hard to find continuing evidence of discrimination. In 1965, when the act was passed, the black-white enrolment gap in Mississippi, for example, was 7% to 70%. By 2004, that had reversed—the black enrolment rate was nearly 4% higher than white enrolment. The majority on the court took this as evidence that the pre-clearance process was no longer required.

But critics at the time noted that the court’s argument that the act had worked was instead strong evidence of the risk to voting rights if it was dismantled. Their fears were quickly realised. Within two hours of the Supreme Court decision in 2013, Texas’s attorney-general said the state would reinstitute a strict voter ID policy that had failed pre-clearance. A day later, North Carolina revised a bill to tighten its own ID laws.

Both laws were later struck down by courts as discriminatory, but the process took years. Since the 2013 Supreme Court decision, civil rights groups and the federal government have had to file suit against potentially discriminatory voter laws after the fact, and the burden of proof is now upon them to demonstrate discriminatory impact. The Supreme Court also denied injunctions to delay implementation of the laws until after the cases were determined, with the result that the restrictions were operative during elections including the 2014 vote for federal House and Senate seats.

The passage of laws and regulations likely to disproportionately impact minority voters has taken off across America. Country-wide, the number of states requiring identification to vote has climbed from 14 in 2000 to 33 in 2016, for example. Nine states have introduced strict photo ID standards. Charles Stewart, a political scientist from the Massachusetts Institute of Technology, has found that black and Latino voters are particularly likely to lack such ID, and are disproportionately likely to be asked for it at polling stations.

The impact of new ID laws, voter purges and limits to voting times on actual votes cast by minority electors is complex to determine and debatable. But voter registration and turnout amongst blacks and Hispanics both dropped nationwide between 2012 and 2016, and while black turnout in North Carolina increased by 1.8% in 2014 compared to prior elections, that was a marked decline in the rate of growth over previous election cycles.

Even if the size of the cost in terms of successful voter suppression is arguable, experts tend to agree that that such laws have few benefits. The major argument in favour of strict voting requirements is that they reduce significant voter fraud. But repeated attempts to measure the problem suggest fraud is extremely rare. In 2011 a survey by the Republican National Lawyers Association could find only one or two cases in each of 21 states over the period 2000-2010, for example.

The Commission on Civil Rights Report is officially directed at the president, vice president and Speaker of the House. It is not clear how much these three Republican men will share the commission’s concerns or seek to address the problem the report highlights. Just 14% of registered Hispanic voters and 3% of black voters identify as members of the Republican Party. And Mr Trump in particular has frequently reiterated his baseless theory that voter fraud is widespread.