The California State Teachers’ Retirement System hired a coordinator to shepherd its effort with other big U.S. investors to engage gun manufacturers and sellers to make firearms safer and expand the coalition.

Michael Weston started May 13 as public engagement manager. Weston, 48, came from the California Department of Social Services, where he spent 13 years, most recently as deputy director of public affairs and outreach programs. Previously he worked in television news.

Several of the pension funds among the 13 investors that announced their joint initiative in November are located in states where mass shootings have occurred, including California and Florida. Victims of the 2017 shootings in Las Vegas included members of Calstrs, the second-largest U.S. pension fund, with $234 billion under management as of April 30.

Large investors are beginning to collaborate more, especially in areas of risk on a global scale, said Kirsty Jenkinson, Calstrs’s director of sustainable investment and stewardship strategies.

“We’re trying to mitigate risk relative to the safety practices around the use of firearms,’’ she said in an interview.

The investor group held almost $5 trillion under management as of November. In addition to pension funds, it includes State Street Global Advisors, Nuveen and retirement systems representing the Methodist and Roman Catholic churches.