Justice Department officials say no decision has been made about whether the federal government will file separate charges against Robert Dear, the man accused of the shooting attack at a Colorado Springs Planned Parenthood clinic on Friday.
State officials will pursue murder charges, and Colorado is a death penalty state, though the governor has imposed a de facto moratorium on executions.
"This is a state case, and we are here to strongly support the state prosecution," said Jeff Dorschner, a spokesman for Colorado's U.S. Attorney, John Walsh.
A possible federal charge would be violating the Freedom of Access to Clinic Entrances Act, known as FACE, passed in 1994. Violations that lead to death carry a maximum penalty of life in prison. Such a charge was used to prosecute James Kopp, who shot and killed a New York abortion doctor in 1998.
Kopp was also convicted on state charges.
Another possible federal charge is violating a statute that bars interfering with programs receiving federal funds. That law carries a maximum sentence of death.
Officials say the Colorado Springs attack was not a hate crime.
Under federal law, a hate crime is an attack on a person or people on account of their race, color, religion, national origin, or sexual orientation.
Depending on what the investigation eventually reveals, the act could be considered an act of domestic terrorism.
Under federal law, domestic terrorism is defined as "acts dangerous to human life" that appear to be intended "to intimidate or coerce a civilian population" or "to influence the policy of a government by intimidation or coercion."
This attack may well fit that definition, but that classification does not automatically invoke any specific charges.
Bottom line, government officials say: the Justice Department could choose to call it an act of terrorism, but the likely federal charge would be under the FACE Act or the civil rights law barring attacks on federally protected activities.