House Democrats on Tuesday will introduce a bipartisan bill to expand background checks for gun purchases, following on Speaker Nancy Pelosi’s Day One pledge to tackle gun violence.

The legislation will expand background checks for guns bought online and at gun shows, but it excludes “reasonable exceptions” for gun transfers among family members. It will be introduced on the anniversary of the Jan. 8, 2011, mass shooting in Tucson, Ariz., that left former Rep. Gabby Giffords seriously wounded.