The 15-year-old schoolboy was fatally shot twice in the head in Creggan in July 1972.
The Foyle MLA said that the Hegarty family deserve justice and accountability for what happened to Daniel after an inquest in 2011 found that he posed no risk to soldiers during ‘Operation Motorman’.
He said: “The murder of Daniel Hegarty is yet another example of a horrendous and cruel crime committed against a teenager who posed no risk to anyone.
“Daniel and his cousin Christopher were both shot in the head close to their homes in Creggan, according to an inquest jury, with no warning and no attempt to provide medical assistance.
“The Hegarty family have had to endure interminable delays for inadequate investigations. Now they have the opportunity to finally secure justice for Daniel.
“The British State has gone out of its way to deny truth, justice and accountability for Daniel, like so many others. That must come to an end,” added Mr Eastwood.