There are several arguments that point to different people.
1. Abigail Williams could be worthy of blame. We see in the first Act that she manipulates the girls into helping her lie about what went on in the forest prior to the start of the play. It is in this same intimidating mood that the girls follow her lead in beginning to call out names of who they "saw" with the Devil in the end of that Act. Her dominance continues as the play unfolds and the girls are required to attend court as if they have a special ability to identify those who are bewitched.
2. The adults who trusted Abigail and the girls could certainly deserve blame. Because they gave the girls this power, they believed the girls actions more and more. In fact, when real evidence was brought to court, the court officials believe the girls' spectral evidence over the hard and tangible evidence along with honest and trustworthy testimony. Danforth and Hathorne would have been dis-barred in today's societies for allowing what happened to happen.
3. Reverend Parris was just trying to protect his reputation. But, his actions set this chain of events in motion. If he could have just accepted what the girls did, Abby might not have gone to all of those lengths to lie about the situation.
4. The Putnams are traditionally considered a party who influenced the girls. Their daughter Ruth was in with the group and reportedly helped influence along with Abby. The Putnams did not get along with many people of the town because their choice for a new minister was not chosen. Additionally, they had land battles with the Nurses and the Proctors. They had motive to see members of those families killed.
The only person who influenced some of the killing who does not share any amount of the blame is John Hale. He worked throughout the entire last Act to free those who were in jail. Now, he didn't try to help them escape, but he certainly tried to convince the court that what they were doing was wrong.