As policymakers wrestle with how to handle the digital remains that people leave behind on sites like Google and Facebook after they die, a new state law expanding access to the deceased’s accounts could set a national trend.

Delaware Gov. Jack Markell has signed into law a measure giving estate attorneys and other fiduciaries more control of their deceased clients’ digital data.

The law, which takes a novel approach, deals with the sensitive issue of what to do when people are outlived by their email and social media accounts, sometimes to the dismay of loved ones who lack access. The law extends access to executors authorized to carry out the instructions of a person’s will. The executor can then transfer email and other data to a family member but isn’t required to.

The statute could conflict with a federal law passed by Congress in 1986 that forbids consumer electronic-communications companies from disclosing content without its owner’s consent or a government order, according to DLA Piper partner Jim Halpert, who co-runs the firm’s global data protection, privacy and security practice.

About 10 states have considered versions of the legislation approved in Delaware, said Mr. Halpert, who is also the general counsel of the State Privacy and Security Coalition, an industry group that includes Google Inc. and Facebook.

Mr. Halpert, whose coalition had opposed the bill, said it raises privacy concerns.

The executor of an estate already has access to letters that belonged to the deceased. The bill, though, removes hurdles an estate attorney or other fiduciary may have when they want to search through emails and deal with old debts or accounts that need to be closed.

Mr. Halpert said an email archive might contain sensitive personal information, such as correspondence with clergy or a doctor, that the deceased might not have wanted disclosed.

“People send a lot more emails than letters, and emails are often more unfiltered than letters,” he said.

Google and Facebook did not immediately respond to requests for comment Wednesday.

In another development that raises similar concerns, Twitter this week said it would remove images of deceased individuals at the request of family members, adopting the policy days after Robin Williams’s daughter publicly complained about being sent disturbing photo-shopped images of her father’s death.

Earlier this summer, the Uniform Law Commission, a group appointed by state governments to draft and lobby for new state laws, approved a “Uniform Fiduciary Access to Digital Assets Act,” upon which the Delaware law is modeled.

A note attached to the Delaware legislation said it recognizes “that an increasing percentage of people’s lives are being conducted online and that this has posed challenges after a person dies or becomes incapacitated.”

Ars Technica, which reported on the legislation, has more background on its potential reach:

For now, the state’s version of UFADAA only applies to residents of Delaware, one of the smallest states by population and land area. If other states don’t follow suit soon, people creating family trusts could conceivably use this Delaware law to their advantage, even without residing in Delaware. However, even though many tech companies (including Twitter, Facebook, and Google) are incorporated there, they will not be affected by the new law.

Daryl Scott, a Delaware state lawmaker who sponsored the bill, told Ars Technica that it will help “protect the rights and interests of the average person in the face of a rapidly evolving digital world.”

Google, in a co-signed industry letter from July urging the governor to veto the bill, said it already allows users to decide if they want their accounts transferred or deleted if they become inactive. The bill “ignores” these customer options, the letter said.