HARTFORD, Conn. — The repeal of capital punishment in Connecticut came too late for Richard Roszkowski, whose death penalty trial is set this year for killing three people in Bridgeport.

The case will be closely watched as a possible test of the new law that is supposed to apply only to future crimes.

The repeal measure signed into law Wednesday by Gov. Dannel P. Malloy preserves the death penalty for the 11 inmates on Connecticut’s death row and for pending cases like Roszkowski’s.

With challenges expected from defense lawyers in those cases, Chief State’s Attorney Kevin Kane and Chief Public Defender Susan Storey say state courts likely will decide whether the repeal violates the rights of death row inmates and people with pending capital felony cases.

“There are very strong arguments that certainly will be made that any future executions would be unconstitutional,” Kane said.

A new argument raised by the repeal, legal experts say, is whether it violates the constitutional right to equal protection by differently treating two groups of people — those who committed capital crimes before the repeal and those who committed such crimes afterward.

It’s not clear if Roszkowski’s public defenders will use the repeal law to challenge the state’s attempts to put him on death row. Michael Courtney, supervisor of the public defenders’ capital defense unit, declined to comment on Roszkowski’s case, but said officials in his office will meet soon to discuss the potential effects of the new law.

The state has about a dozen pending capital felony cases, although the death penalty is not being sought in all of them. Another case that may challenge the repeal is an appeal by nearly all the state’s death row inmates who allege the death penalty is arbitrary and racially biased. That case is set to go to trial in June.

Roszkowski, 47, a former Trumbull resident, was convicted of capital felony and murder in 2009 and sentenced to lethal injection for gunning down a man, woman and 9-year-old girl on a Bridgeport street on Sept. 7, 2006. But the trial judge later threw out the death sentence because of a mistake in the jury instructions and ordered a new penalty phase, which is set to begin with jury selection in June.

Prosecutors said Roszkowski killed ex-girlfriend Holly Flannery, 39, her daughter Kylie and his former roommate Thomas Gaudet, 38. Witnesses testified at trial that Roszkowski stalked Flannery after she broke off their relationship and falsely believed Gaudet was having an affair with her.

Opinions in the legal community are mixed as to whether the repeal will have any impact on current death row inmates and pending capital felony cases.

In testimony submitted to the legislature’s Judiciary Committee in March, the Quinnipiac University School of Law Civil Justice Clinic said repealing the death penalty for future murders would have no effect on current or past cases. The clinic noted that the state Supreme Court upheld the constitutionality of the death penalty in November.