A cluster of recent bailouts of ailing European lenders shows how governments are getting around post-financial crisis rules meant to make sure investors and shareholders take losses as a condition of receiving taxpayer funds.

It is a continuation, critics say, of Europe’s old habit of injecting public money into the financial system as a first resort, many times keeping zombie banks alive and prolonging the painful cleanup of the sector.

Italy’s government approved last month an emergency decree granting a lifeline of up to €900 million ($1 billion) to Banca Popolare di Bari SCpA, a cooperative bank in the country’s south that has struggled with loan losses from a weak economy. It follows other episodes in which Italian authorities also worked around rules to spare debtholders and even some shareholders, many of whom are local retail investors.

In Germany, state owners of troubled bank NordLB recently received the go-ahead from the European Union’s competition authority for a €3.6 billion rescue package after they shot down an attempt by U.S. private-equity firms Cerberus Capital Management and Centerbridge Partners to buy a stake in the lender. NordLB has struggled for years amid heavy losses in its shipping loan portfolio. Without the rescue, its subordinated debtholders would be on the hook.

“We are seeing a lot of creativity going on to avoid resolutions,” said Nicolas Véron, a senior fellow at Bruegel, a Brussels-based think tank. Mr. Véron said bailing out banks weighs on governments’ financials, which in turn can trigger a sovereign crisis that will hurt the banks, in an endless vicious cycle.