London (CNN) -- The widow of poisoned Russian spy Alexander Litvinenko asserted Tuesday that only a public inquiry will bring her justice in the death of her husband. "I still believe in British justice. It's not easy because I didn't expect this long wait," Marina Litvinenko said outside the Royal Court of Justice after a pre-inquest hearing Tuesday. Marina Litvinenko wants a public inquiry instead of an inquest, which, in Britain, is a proceeding to establish the facts around a sudden or unexplained death. A public inquiry is a different proceeding that would "enable the fullest possible investigation" into Alexander Litvinenko's death and, unlike an inquest, can receive evidence behind closed doors, the coroner said during Tuesday's hearing.
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Widow of Alexander Litvinenko says an expanded investigation would bring justice
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That proceeding is called a "public inquiry" in Britain
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The coroner asks for a public inquiry instead of an inquest
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National security matters can be discussed behind closed doors in public inquiry
What we do know is that the British government doesn't want to get into detail about how they know about it, and that to me suggests that they were tapping Russian phones, reading @placeholder diplomatic communications, bugging Russian officers."