Lyra McKee’s partner said she understands why people are afraid to speak out about the 29-year-old’s murder.
Sara Canning said people must understand the hold some groups have over communities in Northern Ireland.
“People can be afraid sometimes to speak up, and I understand that,” she said.
The New IRA said its members were responsible for the killing.
Nine people have since been arrested and released in connection with the murder.
Ms Canning said she is comfortable with the pace of the police investigation, if it means the right person is imprisoned for Ms McKee’s murder.
“We live in Northern Ireland, we have seen how many miscarriages of justice there have been, that’s not something I want,” she told BBC Radio Foyle.
“I want the right person behind bars for the crime they committed.”
In the days after Ms McKee’s murder, more than 140 people provided images, footage and other details through the police’s dedicated Major Incident Public Portal.
Ms Canning said she accepted that fear prevented some from coming forward.
“A lot of people have criticised why more people haven’t come forward, and I have to explain to them, you don’t understand the way of life in those communities,” she said.
“You don’t understand the hold these people have over their communities.”
She said her partner’s killer must be having difficulties coming to terms with guilt.
“If that was a young person who murdered Lyra, then that is the rest of his life that he is tarred with that brush of being a murderer. It is the rest of his life that he has to carry it.
“How do you rationalise that?
“How do you look someone in the eye knowing you have killed someone belonging to them? I can’t imagine being able to rationalise it or having the gall to walk around with your head held high knowing what you have done.”
Ms Canning was speaking to BBC Radio Foyle as part of a series marking the 26th year of Foyle Pride.
“Pride is a protest and this year we are kind of doing it as a protest around the general mood in society,” Ms Canning said.
“We are regressing in a lot of ways. Lyra’s murder shows that. We have gone back to a dark place but it’s reversible, it can be turned around.”