In a brazen killing caught on videotape, a gunman chased Escobedo and shot her at close range in front of the governor's office building in the capital of Chihuahua state.
The slaying drew condemnations from politicians and human rights activists and appeared to be fresh evidence of the impunity with which criminals operate across much of Mexico.
Amnesty International blamed "the negligence of state and federal authorities" for what it called reprisal attacks against rights activists and relatives of crime victims.
"The deficiencies of the judicial system in cases of murdered women and girls have been demonstrated once again," the group said in a statement.
Escobedo's 16-year-old daughter, Rubi Frayre, was slain and dismembered in 2008. The main suspect was her live-in boyfriend, Sergio Barraza, who was captured a year later in the state of Zacatecas.
Although Barraza confessed to the killing, he was exonerated in May by a three-judge panel that found insufficient evidence after a US-style trial with oral arguments held in the state capital, also called Chihuahua.
A separate court reversed the verdict, finding Barraza guilty, but he remains at large.
Escobedo loudly denounced the first court's ruling and had begged state authorities for justice. This month, she planted herself in front of the governor's office.
Escobedo said she had received threats from Barraza and his family but refused to hide.
"What's the government waiting for - that he come and finish me?" Escobedo had asked in an interview outside the governor's palace posted on a website. "Then let him kill me, but here in front to see if it makes them ashamed."
Chihuahua Governor Cesar Duarte said Escobedo had gathered evidence that Barraza was in Zacatecas with members of the Zetas drug gang. Authorities indicated that Barraza was a suspect in the mother's slaying.
Mr Duarte said he would seek the removal of the three judges in the case and ask to have them stripped of immunity from possible prosecution.
"[Barraza] confessed to the killing and reported the place where the remains of Mrs Escobedo's daughter could be found. This is what no one can understand - the irresponsibility of these judges who set free a highly dangerous subject," mr Duarte said in a radio interview.
The video, aired on Mexican television, shows a dark-clad man chasing Escobedo in the darkness as she sprints across the street toward the governor's office, which was closed at the time. Escobedo flops to the sidewalk as the shooter races to jump into a waiting sedan.
Chihuahua has been a pioneer in Mexico in rolling out a new system of trials, which resemble US adversarial proceedings because prosecutors have to prove cases in open court.
The new system means tougher standards of evidence than under Mexico's traditional trials, which are decided behind closed doors by judges relying largely on written filings from both sides