Illinois Sen. Dick Durbin on Thursday blasted the card network-dominated group that sets the standards for chip-enabled plastic payment, accusing it of mishandling the rollout of more secure credit and debit cards, lacking transparency and refusing, at the expense of retailers, to promote PIN authentication.

EMV stands for EuroPay, MasterCard and Visa, but for consumers it mostly means a card with a chip in it that is more secure than the magnetic strips that have until last year prevailed in the United States. Some stores have adopted the new technology, others have not.

Durbin, a longtime crusader against the major credit card companies, wrote a March letter demanding that EMVCo, the group that sets standards for the chip technology, explain its governance and decisionmaking in light of the snags that EMV cards have run into since their introduction in 2015.

He said the transition to EMV chips in cards in the United States has been "plagued by problems," such as merchants not being able to use EMV card readers because of a backlog in the software certification process and consumers facing longer wait times at retail counters.

EMVCo, founded in 1999 by Visa and MasterCard, is now run by six companies: American Express, Discover, MasterCard, Visa, Japanese payment network JCB and Chinese payment network UnionPay.

Merchants and payment networks can serve in an advisory role in the group, EMVCo executive Brian Byrne wrote in his response to Durbin's March letter, but the executive committee is made up of card company representatives.

Durbin latched onto that in a letter Thursday, arguing that the group lacks "diverse stakeholder voices" and that the problems with the EMV rollout are thus unsurprising.

"It appears that EMVCo is currently run by the big card networks for the big card networks," Durbin wrote.

Durbin also criticized the group for not taking a position on PIN authentication, which retailers want to require. Major retailers are battling the credit card companies in court over whether they can require customers to enter a PIN.

The card companies charge a little more per transaction for signature-based purchases, so retailers want as many transactions as possible to be authenticated with a PIN. Wal-Mart sued Visa over the matter on Tuesday.