SEATTLE (AP) — A Democratic senator from Connecticut is writing a bill that would stop the practice of employers asking job applicants for their Facebook or other social media passwords, he told The Associated Press on Thursday.

U.S. Sen. Richard Blumenthal said that such a practice is an "unreasonable invasion of privacy for people seeking work."

"These practices seem to be spreading, which is why federal law ought to address them. They go beyond the borders of individual states and call for a national solution," said Blumenthal, who first spoke to Politico on Wednesday.

The AP reported this week that some private and public agencies around the country are asking job seekers for their social media credentials. The practice has alarmed privacy advocates, but the legality of it remains murky.

Experts say the terms of service for Facebook and other sites don't carry much weight in these cases. The Department of Justice regards it as a federal crime to enter a social networking site in violation of those terms, but the agency said during recent congressional testimony that such violations would not be prosecuted.

The practice is more prevalent among public agencies, such as police departments and 911 dispatchers.

Blumenthal said his bill will have some exceptions, such as some federal and local law enforcement agencies, or national security departments. He said it would include private companies with government contracts for highly classified work.

Lori Andrews, a law professor at IIT Chicago-Kent College of Law specializing in Internet privacy, is concerned about the pressure placed on applicants, even if they voluntarily provide access to social sites.

"Volunteering is coercion if you need a job," Andrews said.

Blumenthal said he has heard complaints from constituents about the practice and read the AP's news report. A state senator from San Francisco said he also was prompted by the AP's report to act immediately on legislation.

California Sen. Leland Yee, a Democrat, was aware of complaints similar to those outlined in the report and had been considering introducing legislation next year, said his spokesman, Adam Keigwin.

Yee said he instead plans to amend an existing bill in coming days to prohibit employers from asking current employees or job applicants for their social media user names or passwords. That state measure also would bar employers from requiring access to employees' and applicants' social media content, to prevent employers from requiring log-ins or printouts of that content for their review.

The prohibition would apply to both public and private employees, Keigwin said.

Blumenthal said he has yet to reach out to colleagues and U.S. Senate leadership, but that he expects to have wide support for the federal bill.

"Privacy is not a partisan issue," Blumenthal said.